NOTE: Replacing the diaphragm may not always resolve your problem as the fault could be with the valve itself but it is a cheap way to try and resolve and is usually successful. If the cistern empties then the problem is with the flush valve seal or flush valve itself.
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Pro Side Entry Inlet Valve Side Entry Inlet Valve Brand New Pro Side Entry Inlet Valve 1/2 Inch For Cistern - Brass Shank
Aliexpress UK
HIGH QUALITY MATERIAL: Made of original rubber material, it has excellent water resistance and flexibility.
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Bath Thermostatic Faucet shower switch Valve Core cartriage shower valve cartridge Button Type Recessed Shower Valve Core 1pcs
Aliexpress UK
Dual Flush Valve Diaphragm Seal And Clip. DUAL FLUSH VALVE DIAPHRAGM SEAL & CLIP. 1xDUAL FLUSH VALVE DIAPHRAGM SEAL & CLIP. Compatible with the following flush valves .
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Plastic 4mm / 6mm / 8mm / 12mm For Gas Water Non-Return For Fuel Air Liquid Valves One-way Lnline Check Valve Water Stop Valve
Aliexpress UK
NOTE: Replacing the diaphragm may not always resolve your problem as the fault could be with the valve itself but it is a cheap way to try and resolve and is usually successful. cistern empties then the problem is with the flush valve seal or flush valve itself.
eBay
Translucency Durable 4mm / 6mm / 8mm / 12mm White Non-Return For Gas Water Water Stop Valve Valves One-way Lnline Check Valve
Aliexpress UK
Simply twist the valve in an anticlockwise direction and the unit just lifts out.
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Brass Thermostatic Mixing Valve Constant Water Temperature Shower Faucet Valve Thermostat Bathroom Kitchen Tap Valve
Aliexpress UK
GEBERIT TWICO-1 DUAL FLUSH VALVE BODY ONLY. Used by many manufacturers like Kohler,Ideal Standard, Duravit, RAK. NOTE: BODY ONLY.
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Faucet Valve Core Kitchen Basin Hot And Cold Water Faucet Ceramic Valve Core 30/35/40MM Shower Mixing Valve Core Accessories
Aliexpress UK
Durable Flush Valve Seal & Clip Set - 6 Pcs for Easy Repairs. Our set is engineered to stop unwarranted leaks and eliminate the frustration of "ghost flushing" once and for all. Easy to install, no need for a plumber—restoring your toilet to its optimal performance has never been so effortless.
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20/25/32/40/50mm PE Pipe Faucet Diverter 3-Way Ball Valve Plastic Valve Ball Valve Garden Lawn Irrigation Water Pipe Fittings
Aliexpress UK
Ideal Standard / TWICO / Geberit Diaphragm Washer for Outlet Flushing Valve.
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Red Handle Valve 8mm 10mm Hose Barbed Ball Valve Inline Brass Water Oil Air Gas Straight Shutoff Ball Valve Pipe Fittings
Aliexpress UK