Thermostatic Radiator Valve (TRV) Spares identifies some of the spares associated with the Manual and Thermostatic Radiator valves.

T100MZ actuator with remote sensor and remote set point adjustment. ZS100 Range stops for thermostatic heads. Packed 10 pieces.
ZS100 Range stops for thermostaticheads. Packed 10 pieces.
H100 - ZE Manual head with locking ratchet. Pack of 25.
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T9002W0 Replacement thermostatic head.
Stylish Valencia TRV heads with a range of different finishes   Chrome finish designed for designer radiators in bathrooms and other areas   Brushed Chrome finish  to suit all modern decors   Black and chrome suitable for kitchens and other areas where dark  work tops or cupboards are...