This diaphragm/washer suits the newer 'Twist lock' inlet valve; that requires a 45 degree turn to twist off the connection to see the diaphragm. Another thing to check is to turn your old diaphragm over to look at the bottom.
eBay
Pro Side Entry Inlet for Valve 1/2" Connect For Cistern Brass Shank Single Float
Aliexpress UK
Twyford Toilet Cistern Kit, Single Flush Syphon, Ball, Side Inlet Valve, Flush Chain Pull CF7010CP. Complete Kit: Includes syphon, ball float, inlet valve, and flush chain.
eBay
Dc 12V 220V Plastic Electric Solenoid Valve Normally Closed Pressure Solenoid Valve Inlet Valve Inlet Flow Switch
Aliexpress UK
Twyford Brand New Geniune Cistern Ball Inlet Valve Side Entry Valve
eBay
Cnkb Water Inlet Solenoid Valve Water Boiler Valve External Thread 1/2" Fpd-90A-12V Water Heater Interface 20mm Inlet Valve
Aliexpress UK
Siamp Compatible Cistern Valve Inlet fill valve Diaphragm washer. Fits all siamp ball valves. Suits all Siamp bottom and side inlet filling valves. Cistern Inlet Filling Valve Diaphragm. Washer Seals.
eBay
1PC 220V-240V 3/4''12mm dishwasher water inlet valve Solenoid valve Water inlet valve for Ice machine Coffee machine
Aliexpress UK
Enhance your toilet’s flushing system with the VeeBath Pro Bottom Entry Fill Valve, designed for superior performance, durability, and versatility. With an adjustable height range from 8"" to 11.5"", it’s compatible with various toilet cisterns.
eBay
Stainless Steel Triangle Valve Hot Cold Inlet Valve Toilet Water Stop Valve Water Heater Valve Kitchen Sink Basin Triangle Valve
Aliexpress UK
1/2" bottom entry toilet fill valve Specification: Universal design, bottom entry, quiet water filling Stable performance under different perssures ranges from 0.13bar to 16bar G 1/2" brass connector / tail Adjustable height 10-13" Two-piece float, momentary shut-off Anti-siphon structure Quality: WRAS certified CE ISO 9001 UPC 12 month warranty backed up by SASCOM Products QUALITY Assurance.
eBay
Brand New High Quality Hot Cistern Fill Valve Accessories Bottom Siphon Spare Universal Cistern Fill Flush Valve
Aliexpress UK
Suits all Siamp bottom and side inlet filling valves. Toilet Cistern Inlet Washer Seal Diaphragm. Inlet valve not included.
eBay
Brass Angle Valve Chrome Black Rose Gold Inlet Valve Bathroom Single & Double Outlet Valve G1/2 Water Stop Valve Toilet Kitchen
Aliexpress UK
: AS1172.2 - WMKA20080. : This valve features a versatile dual flush system, allowing you to choose between a full flush for solid waste or a half flush for liquid waste, making it a perfect ally in conserving water while maintaining excellent performance.
eBay
Brass Angle Valve Chrome Black Rose Gold Inlet Valve Bathroom Single & Double Outlet Valve G1/2 Water Stop Valve Toilet Kitchen
Aliexpress UK