Search UK public tenders and contract notices

Official notices, one row per procedure. Filters use published facts only: delivery region from the notice, buyer type from the official classification, route and agreement type as published, never a Tenderline score.

Syntax:"exact phrase"cleaning OR cateringsoftware -consultancy(cleaning OR catering) AND hospitalgovern*admin+defenceocds-…

More filters
How
What
WhoA buyer type and a specific contracting authority are alternatives: choosing one clears the other.
When & money
Reset

All records

Showing 1–44 · every procedure in the catalogue, any stage.

  1. Closes · 50 days leftCompetitive flexible procedureFrameworkUtilitiesSME suitable

    PRO005084-Services-Framework-DNM Linear Monitor Installs

    United Utilities Water Limited · North West England

    The purpose of this framework is to appoint three end-to-end delivery partners to support the continued deployment of battery-powered level monitoring across the wastewater network during the mid to late stages of AMP8. The programme is exp…

    • Environmental monitoring other than for construction
    • Added-value database services
    • Calibration services
    • +15
    Value
    £25mceiling, not a contract size
    Term
    3 yearsup to 8 years with extensions
    Submit via
    EU-Supply (CTM)public page
    Published
    #077b8b
  2. Awarded · Open procedureFramework12 lotsSME · VCSE suitable

    Regenda Ltd Works and Services Framework

    Regenda Limited · North West England, Yorkshire and the Humber, Wales (Cymru)

    Regenda Limited is establishing construction works and services framework in partnership with Rise Construction Framework Ltd. The framework is being established as a closed framework. The framework will operate across the following geograp…

    Awarded to AC Group, AHR BUILDING CONSULTANCY LIMITED, AJF ENGINEERING CONSULTANTS LTD +95 more · 12 awards

    • Construction work
    • Architectural, construction, engineering and inspection services
    • Building completion work
    • +7
    Value
    £428mceiling, not a contract size
    Term
    4 years
    Submit via
    mytenderslogin required
    Published
    #05d929
  3. AwardedBelow threshold - limited competition

    Laser Interlock Control Systems

    Mayor's Office for Policing and Crime · Central government · Greater London

    18 x Laser Interlock Control Systems (manufactured to specification agreed by the Authority in accordance with the EN ISO 13849-1 standard) including delivery, installation, commissioning, and demonstration

    Awarded to LASER OPTICAL ENGINEERING LIMITED

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #06cd9c
  4. AwardedBelow threshold - limited competition

    Nuneaton Justice Centre BMS Replacement Project

    The Police and Crime Commissioner for Warwickshire · Police & fire · West Midlands

    Please note this contract has been awarded and is NOT a call for competition. The Police & Crime Commissioner for Warwickshire has awarded a contract for the provision of a BMS replacement project at Nuneaton Justice Centre on behalf of War…

    Awarded to AP Mitchell Building Services Ltd

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #06cbd4
  5. Planned · expected · not yet publishedSME suitable

    BMS (Building Management System) Phase 2

    Ravensbourne Limited · Greater London

    The overarching objective of the project is to modernise the existing BMS front-end and communications infrastructure, and to upgrade legacy controllers whilst retaining, where appropriate, the existing field level peripheral control device…

    • Installation services of guidance and control systems
    Value
    £800k
    Term
    15 months
    Submit via
    portal not identified
    Published
    #06c6ad
  6. Closed Open procedure

    BMS (Building Management System) Phase 2

    Ravensbourne Limited · delivery region not published

    Ravensbourne University London is pleased to invite your organisation to submit a tender for the full works package associated with the Ravensbourne University London – BMS Upgrade Project. The project comprises a phased upgrade of the Univ…

    • Installation services of guidance and control systems
    Value
    £950k
    Term
    20 months
    Submit via
    EU-Supply (CTM)public page
    Published
    #06c446
  7. Planned · expected · not yet publishedFrameworkUtilitiesSME suitable

    PRO005123-Services-Framework-Powered Monitors

    United Utilities Water Limited · North West England

    The Service Provider shall deliver a programme of predominantly electrical and instrumentation services to support the design, supply, installation, modification, operation, and maintenance of low voltage power monitoring solutions across U…

    • Systems and technical consultancy services
    • Added-value database services
    • Calibration services
    • +25
    Value
    £1ceiling, not a contract size
    Term
    3 yearsup to 7 years with extensions
    Submit via
    portal not identified
    Published
    #06b5e9
  8. Planned · expected · not yet publishedFrameworkUtilitiesSME suitable

    PRO005084-Services-Framework-DNM Linear Monitor Installs

    United Utilities Water Limited · North West England

    The purpose of this framework is to appoint one or more end-to-end delivery partners to support the continued installation of battery powered level monitoring through AMP8. This regional programme will deliver approximately 15,000 monitors …

    • Environmental monitoring other than for construction
    • Added-value database services
    • Calibration services
    • +15
    Value
    £20mceiling, not a contract size
    Term
    3 yearsup to 5 years with extensions
    Submit via
    portal not identified
    Published
    #0697d0
  9. Awarded · Competitive flexible procedureUtilities

    Dynamic Sewer Visualisation (DSV)

    Anglian Water Services · East Midlands, East of England, South East England

    Anglian Water is introducing a new contract for the maintenance and repair of Dynamic Sewer Visualisation (DSV) monitors. These monitors are vital early warning systems that help us detect pollution and flooding risks quickly, protecting bo…

    Awarded to EMR Integrated Solutions, Utilitec Services Limited · 4 awards

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #0690a9
  10. Awarded · Direct award

    Control Systems OEM - ABB Ltd Equipment Service and Maintenance

    Sellafield Limited · North West England

    The provision of maintenance & technical support of in situ control system equipment used by Sellafield Ltd which have been manufactured and supported by the original equipment manufacturer (OEM) - ABB Limited. The scope includes: on-site s…

    Awarded to ABB Limited

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #06689f
  11. Awarded · Direct award

    Control Systems OEM - Schneider Electrical Ltd Equipment Service and Maintenance

    Sellafield Limited · North West England

    The provision of maintenance & technical support of in situ control system equipment used by Sellafield Ltd which have been manufactured and supported by the original equipment manufacturer (OEM) - Schneider Electric Systems UK Limited. The…

    Awarded to SCHNEIDER ELECTRIC SYSTEMS UK LIMITED

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #06691d
  12. Awarded · Direct award

    Control Systems OEM - Rockwell Automation Limited Equipment Service and Maintenance

    Sellafield Limited · Nationwide (UK), North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original equipment manufacturer (OEM) - Rockwell Automation Limited, including: On-site support, brea…

    Awarded to Rockwell Automation Ltd

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #066100
  13. AwardedBelow threshold - without competition

    Renewal of communications contract forRenewal of UK's Argos and Iridium satellite data telemetry for Argo floats

    Met Office · Central government · Nationwide (UK)

    The Met Office have Argo floats out in the oceans transmitting data via the Argos system. Collecte Localisation Satellites (CLS)-Argos are the sole operators of the Argos telecommunications system. ProContract ref. DN805249

    Awarded to Collecte Localisation Satellites (C.L.S)

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #067504
  14. WithdrawnSME suitable

    Dimming and Trimming Streetlighting (Street Lighting Control and Management Solutions)

    London Borough of Lambeth · Local authority · delivery region not published

    A Central control system, and relevant assets to allow for Lambeth’s lighting stock (14,000 columns) to be fitted with sensor devices to allow for remote control/management of lighting infrastructure in real time, which will enable the auth…

    • Installation of road lighting equipment
    • Installation services of airport real-time departures and arrival display screens or boards
    • Installation services of electrical and mechanical equipment
    • +16
    Value
    £3.2m
    Term
    2 years
    Submit via
    portal not identified
    Published
    #051842
  15. Closes · 94 days leftCompetitive flexible procedureUtilitiesSME suitable

    Continuous Water Quality Monitoring (CWQM)

    United Utilities Water Limited · North West England

    At United Utilities, it is our commitment to supply great water to homes and businesses, removing and treating wastewater behind the scenes. We are developing our infrastructure in response to climate, population and lifestyle changes so we…

    • Environmental monitoring other than for construction
    • Added-value database services
    • Calibration services
    • +19
    Value
    £127m
    Term
    3 yearsup to 10 years with extensions
    Submit via
    EU-Supply (CTM)public page
    Published
    #06146f
  16. Award pendingBelow threshold - without competitionUtilitiesSME suitable

    Replacement of outdated Help Point signage

    SE TRAINS LIMITED · North East England, North West England, Yorkshire and the Humber, East Midlands, West Midlands, East of England

    Replacement of outdated Help Point signage with Assistance Point-specific wayfinding signs

    Intended award to TRANS DATA MANAGEMENT LTD

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #060c91
  17. AwardedBelow threshold - without competitionLight-touch

    HARDWARE & LICENCES FOR BMS AND ALARM SYSTEM

    Hull University Teaching Hospitals NHS Trust · Central government · Yorkshire and the Humber

    MITIE LTD ARE UNDERTAKING FACILITIES MANAGEMENT ROLE AT CDC HULL WHICH REQUIRES HARDWARE AND LICENCES FOR BMS AND ALARM SYSTEMS. THIS HAS NOT BEEN COVERED UNDER FM CONTRACT THEREFORE ADDED AS ONE OF COST.

    Awarded to MITIE FM LIMITED

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #059796
  18. AwardedAward procedure without prior publication of a call for competition

    Control Systems OEM Equipment Service and Maintenance

    Sellafield Limited · North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original OEM of the equipment insitu and in use by Sellafield, including: On-site support, breakdown …

    Awarded to ABB Limited

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #050bf0
  19. Planned · expected · not yet publishedUtilities

    Continuous Water Quality Monitoring (CWQM)

    United Utilities Water Limited · North West England

    Water companies have a duty under Section 82 of the Environment Act to protect the environment from the effects of discharges from storm overflows and wastewater treatment works. Water companies are required to monitor the quality of water …

    • Added-value database services
    • Calibration services
    • Data analysis services
    • +19
    Value
    £120m
    Term
    4.5 years
    Submit via
    portal not identified
    Published
    #055712
  20. AwardedBelow threshold - without competition

    Safety Instrumented Function (SIF) to detect imminent flooding of the Brooksby building.

    THE PIRBRIGHT INSTITUTE · South East England

    As part of the Brooksby project, in order to be compliant with Functional Safety standards (IEC 61508/61511), services are required to purchase materials, manufacture a panel, install, and commission a new drainage network Safety Instrument…

    Awarded to Suncombe Ltd

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #055179
  21. AwardedAward procedure without prior publication of a call for competition

    Control Systems OEM Equipment Service and Maintenance Contract

    Sellafield Limited · North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original OEM of the equipment in situ and in use by Sellafield, including: On-site support, breakdown…

    Awarded to Rockwell Automation Ltd

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #050bf3
  22. AwardedAward procedure without prior publication of a call for competition

    Control Systems OEM Equipment Service and Maintenance Contract

    Sellafield Limited · North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original OEM of the equipment in situ and in use by Sellafield, including: On-site support, breakdown…

    Awarded to SCHNEIDER ELECTRIC SYSTEMS UK LIMITED

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #050bf1
  23. AwardedAward procedure without prior publication of a call for competition

    Control Systems OEM Equipment Service and Maintenance

    Sellafield Limited · North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original OEM of the equipment in<br/>situ and in use by Sellafield, including: On-site support, break…

    Awarded to ABB Limited

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #050bef
  24. AwardedBelow threshold - without competition

    Argos and Iridium satellite data telemetry for Argo floats

    Met Office · Central government · Nationwide (UK)

    The Met Office have Argo floats out in the oceans transmitting data via the Argos system. Collecte Localisation Satellites (CLS)-Argos are the sole operators of the Argos telecommunications system. ProContract ref. DN771920

    Awarded to Collecte Localisation Satellites (C.L.S)

    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #050bc5
  25. AwardedOpen procedure

    Term Service Contract for the Maintenance, Periodic Inspection and Servicing, and Installation of Building Energy Management Systems - Retender

    East Riding of Yorkshire Council · Local authority · Yorkshire and the Humber

    The Maintenance, Periodic Inspection and Servicing, and Installation of Building Energy Management Systems in various occupied operational properties within the geographical boundaries of the East Riding of Yorkshire.

    Awarded to E.ON Control Solutions Limited

    • Repair and maintenance services
    • Command, control, communication and computer systems
    • Installation services of guidance and control systems
    • +1
    Value
    £1.2m
    Term
    6 years
    Submit via
    EU-Supply (CTM)public page
    Published
    #0497e5
  26. AwardedAward procedure without prior publication of a call for competition

    BMS Upgrades - Betsi Cadwaladr UHB (West)

    NHS Wales Shared Services Partnership-Procurement Services (hosted by Velindre University NHS Trust) · NHS & health · Wales (Cymru)

    This contract is for the upgrade works required for the Building Management Systems (BMS) at various sites of BCU in the West region as the existing controllers are obsolete. These systems control all the heating, hot water services, ventil…

    Awarded to Honeywell Building Solutions Ltd · 2 awards

    • Installation services of guidance and control systems
    • Command and control system
    • Command and control system, printing, graphics, office automation and information-processing equipment
    • +9
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #03ecdd
  27. Closed Open procedure

    IT Cabling and Hardware

    YORKSHIRE WATER SERVICES LIMITED · Yorkshire and the Humber

    The objective of this Procurement Process is to provide a required range of network infrastructure goods and services to Yorkshire Water (YW). This includes activities such as installation, moves, refurbishment and on-site troubleshooting. …

    • Installation services (except software)
    • Computer equipment and supplies
    • Computer servers
    • +8
    Value
    £2.1m
    Term
    3 years
    Submit via
    portal not identified
    Published
    #04b540
  28. Closed Open procedure

    Tritium Plant Virtual Control Room

    United Kingdom Atomic Energy Authority · South East England

    The requirement is deliver the infrastructure required for a virtual control room for the UK Atomic Energy Authority tritium plant. This includes the supply of the hardware, software and licences, and providing the integration between the c…

    • Computer control system
    • Computer equipment and supplies
    • Industrial control software package
    • +2
    Value
    £400k
    Term
    5 months
    Submit via
    EU-Supply (CTM)public page
    Published
    #049c12
  29. CancelledOpen procedure

    Term Service Contract for the Maintenance, Periodic Inspection and Servicing, and Installation of Building Energy Management Systems

    East Riding of Yorkshire Council · Local authority · Yorkshire and the Humber

    The Maintenance, Periodic Inspection and Servicing, and Installation of Building Energy Management Systems in various occupied operational properties within the geographical boundaries of the East Riding of Yorkshire.

    • Repair and maintenance services
    • Command, control, communication and computer systems
    • Installation services of guidance and control systems
    • +1
    Value
    £1.2m
    Term
    6 years
    Submit via
    EU-Supply (CTM)public page
    Published
    #047865
  30. Planned · expected · not yet published

    Tritium Plant Virtual Control Room

    United Kingdom Atomic Energy Authority · South East England

    UKAEA is currently designing a new tritium processing plant, referred to as the Hydrogen-3 Advanced Technology (H3AT) Facility. The H3AT Facility will be located on the UKAEA Culham site in the existing H3AT building. A virtual control room…

    • Computer control system
    • Computer equipment and supplies
    • Industrial control software package
    • +2
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #0486e1
  31. Closed Open procedure

    Procurement for the provision of Replacement of House PA System at The Hexagon Theatre, Queens Walk, Reading, RG1 7UA

    Reading Borough Council · Local authority · South East England

    This contract is for the supply and installation of a complete new main PA System and sound desk at The Hexagon Theatre, Queens Walk, Reading, RG1 7UA. . The project includes the supply and installation of all new cabling and any additional…

    • Electrical machinery, apparatus, equipment and consumables; lighting
    • Installation services of guidance and control systems
    Value
    Not published
    Term
    3 months
    Submit via
    portal not identified
    Published
    #04505f
  32. Closed Negotiated procedure with prior call for competition

    L24007-T-CL Airfield Ground lighting (AGL) control systems Service and Support

    LONDON LUTON AIRPORT OPERATIONS LIMITED · East of England

    - This is a requirement for a five (5) year requirement for the service, maintenance, call out, and "works" on the sites Airfield Ground lighting (AGL) control systems.

    • Installation services of guidance and control systems
    • Installation services (except software)
    • Installation services of electrical and mechanical equipment
    Value
    £335k
    Term
    5 years
    Submit via
    portal not identified
    Published
    #044b29
  33. AwardedRestricted procedureFramework4 lots

    Site Security Maintenance & Upgrade Services Contract

    Nuclear Restoration Services Limited · Nationwide (UK), North West England

    Contract to provide Site Security Maintenance & Upgrade Services for the NRS Magnox Estate

    Awarded to Enigma Security Solutions, See Contracts Finder Notice for full supplier list, Total Security Protection Limited · 3 awards

    • Security services
    • Accumulators, primary cells and primary batteries
    • Alarm systems
    • +87
    Value
    £3.0bnceiling, not a contract size
    Term
    3.5 years
    Submit via
    Jaggaerlogin required
    Published
    #02a8ec
  34. Planned · expected · not yet published

    Drones Sensor Network for the Solent Transport FTZ Programme

    Portsmouth City Council · Local authority · South East England

    Portsmouth City Council on behalf of Solent Transport is undertaking a soft market testing exercise in preparation for tendering a contract for the supply and installation of sensors for Solent Transport FTZ drone sensor network. The Counci…

    • Sensors
    • Data transmission services
    • Data-communications equipment
    • +5
    Value
    £250k
    Term
    Not published
    Submit via
    portal not identified
    Published
    #040d86
  35. Closed Open procedure

    TIAL-PROC-0090 Radar Display System

    Tees Valley Combined Authority · Local authority · North East England

    Teesside International Airport (TIA) Air Traffic Control (ATC) are inviting proposals to replace the current Cobham RDS1600 Radar Display System (RDS) with a new system. The aim of this document is to provide technical detail to allow a pro…

    • Installation services of guidance and control systems
    • Radar surveillance equipment
    Value
    £500k
    Term
    9 years
    Submit via
    portal not identified
    Published
    #03ee5a
  36. AwardedOpen procedure

    Building Energy Management System (BEMS) Service and Maintenance

    University of Bristol · Education · South West England

    Buildings Energy Management Systems (BEMS) Trend System specialist to undertake the service and maintenance of the University's BEMS and associated systems and networks

    Awarded to Kendra Energy Solutions Limited

    • Preventive maintenance services
    • Installation services of guidance and control systems
    • Measuring and control equipment
    Value
    Not published
    Term
    3 years
    Submit via
    portal not identified
    Published
    #03aca2
  37. AwardedAward procedure without prior publication of a call for competitionFramework

    Control Systems OEM Equipment Service and Maintenance

    Sellafield Limited · North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original OEM of the equipment in situ and in use by Sellafield, including: On-site support, breakdown…

    Awarded to SCHNEIDER ELECTRIC SYSTEMS UK LIMITED

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #03c694
  38. AwardedAward procedure without prior publication of a call for competitionFramework

    Control Systems OEM Equipment Service and Maintenance

    Sellafield Limited · Nationwide (UK), North West England

    The provision of Maintenance & Technical Support of Programmable Logic Controllers and Control Equipment manufactured and supported by the original OEM of the equipment in situ and in use by Sellafield, including: On-site support, breakdown…

    Awarded to Rockwell Automation Ltd

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #03c556
  39. AwardedAward procedure without prior publication of a call for competitionFramework

    Service and Maintenance of OEM Control Systems Equipment

    Sellafield Limited · Nationwide (UK), North West England

    Provision of Service and Maintenance of OEM's Controls Systems equipment in situ at Sellafield Site. The provision of Tier 0-4 Escalation, response to site (next working day), Corrective Maintenance visits (charged), agreed repairs, Obsoles…

    Awarded to ABB Limited

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #03c546
  40. Planned · expected · not yet publishedDynamic purchasing system

    Building Energy Management System (BEMS) - Smart Technology DPS

    University of Bristol · Education · South West England

    The University of Bristol Campus Division is looking to deliver Smart Technology solutions at scale across its estate buildings to enable the Campus Division and the wider university to meet key strategic aspirations such as carbon net zero…

    • Installation services of guidance and control systems
    • Measuring and control equipment
    Value
    £5.0mceiling, not a contract size
    Term
    Not published
    Submit via
    portal not identified
    Published
    #03ad09
  41. Planned · expected · not yet published

    Continuous River Monitoring

    United Utilities Water Limited · North West England

    Water companies have a duty under Section 82 of the Enviroment Act to protect the environment from the effects of discharges from storm overflows and wastewater treatment works. Water companies are required to monitor the quality of water p…

    • Monitoring and control services
    • Electricity supply installations
    • Industrial process control equipment
    • +8
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #03860f
  42. AwardedAward procedure without prior publication of a call for competition

    (FTUAS) Integration into T23 Combat Management

    Ministry of Defence · Central government · Nationwide (UK)

    Notice of contract awarded for (FTUAS) Integration into T23 Combat Management System

    Awarded to BAE Systems Surface Ships Ltd · 2 awards

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #02fa4d
  43. Planned · expected · not yet published

    Central Line Signalling Incremental Upgrade Project

    Transport for London · Greater London

    Transport for London (TfL) is issuing a Market Sounding Questionnaire (MSQ) as part of the Early Market Engagement (EME) activity for the Central Line Signalling Incremental Upgrade Project (CSIP). The purpose of the MSQ is to improve TfL's…

    • Installation services of guidance and control systems
    Value
    Not published
    Term
    Not published
    Submit via
    portal not identified
    Published
    #02d3a7
  44. Planned · expected · not yet published

    East West Rail Company (EWR Co) CS2 & CS3 Route Wide: Pre-Procurement Market Engagement

    East West Rail Company Limited · Nationwide (UK)

    East West Rail is an ambitious project that involves bringing back into use a section of railway that was closed to passengers in the 1960s, refurbishing existing railway lines between Oxford and Bedford, as well as building brand new railw…

    • Railway construction works
    • Architectural, construction, engineering and inspection services
    • Building installation work
    • +20
    Value
    £0
    Term
    Not published
    Submit via
    portal not identified
    Published
    #02b4f6