Wow, what a brilliant key! At 4.75mm, a snug fit on all my bleed screws. Large physical size of 'wings' give plenty of torque on stiff bleed screws without rounding off the square. I wish that I had had one of these in my toolkit years ago.
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2PCS Radiator Bleed Key Heater Bleed Key Suitable For All Radiators Radiator Bleeder Key Heater Square Key Exhaust Valve Keys
Aliexpress UK
ENHANCED LEVERAGE: The longer handle design provides extra leverage for effortless turning on this Heatlab radiator airer.
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10/6/8pcs Radiator Valve Key Faucet Key Radiator Water Tap Plumbing Bleeder Key Air Vent Central Heating Tool Radiator Bleeding
Aliexpress UK
RADIATOR BLEED KEY - 9 SIZES. RADIATOR PARTS. SQUARE HEAD SIZE. DO TAKE CONSIDERATION FOR THE TAPER AT THE END OF KEY WHEN UNWIDING. (FILE DOWN IF PREFERED).
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Radiator Valve Key Faucet Key Radiator Water Tap Plumbing Bleeder Key Air Vent Central Heating Tool Heater Wrench Black Wrench
Aliexpress UK
Universal Compatibility: Includes 8x4mm, 7x3mm, 7x4mm and 6x6mm to fit most lockshield radiator valves, including Myson Matchmate models.
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1Pcs Key Spanners Radiators Carbon Steel Pagoda Head Valves Key Step Wrench with Square 1/2inch Ratchet Drive Radiators Wrench
Aliexpress UK
RADIATOR BLEED KEY - 9 SIZES. RADIATOR PARTS. SQUARE HEAD SIZE. DO TAKE CONSIDERATION FOR THE TAPER AT THE END OF KEY WHEN UNWIDING. (FILE DOWN IF PREFERED).
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YUANJ 2/5PCS Radiator Exhaust Valve Key Square 5×5mm Radiator Accessories Zinc Alloy Material Socket for Heating Key Tools
Aliexpress UK
These 2 piece radiator bleed keys are designed for use on domestic radiator bleed screws to release air in radiators. They are compatible with standard radiator heating systems and are made of durable materials to withstand regular use. These keys have a square opening that is specifically designed to fit onto radiator bleed screws, making them easy to use and ensuring a secure fit. They are small and compact, making them easy to store and transport. They are an essential tool for anyone who needs to maintain their radiator heating system and ensure that it is working efficiently. With these radiator keys, you can easily release any trapped air and keep your system running smoothly. They are a convenient and reliable tool that every homeowner should have on hand.
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Universal Cross Key Control Cabinet Keys 4-Way Multifunctional Key for Water Electricity Meter Radiator Gas Meter
Aliexpress UK
Horizontal Radiators. Vertical Radiators. White Flat Panel Radiator. Towel Rails. Radiator Valves & Accessories. Can be use on all UK water heating systems(tank fed or combi systems etc.). Without break and leakage after testing with 10 bar pressure.
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Multi Functional Utility Key Wrench Plumbers Key Triangle Cabinet Spanner Key For Radiators Gas Electric Meter Boxes Faucet
Aliexpress UK
2PC CLOCK TYPE RADIATORS KEYS.
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2pcs Radiator Exhaust Valve Key Square 5×5mm Radiator Accessories Zinc Alloy Material Socket For Standard Heating Valves
Aliexpress UK