This thermostatic cartridge assembly is for the ENKI Winchester antique brass Sequential Mixer Shower Valve. Please inspect the technical diagram and the photos carefully to ensure this is the correct thermostatic cartridge you require. If your thermostatic shower handle has become very stiff, or if the water coming out the bath or shower outlet is not constant in flow and temperature the thermostatic cartridge could be at fault. Try replacing the cartridge and the chances are it'll fix the problem. Spare Part: Thermostatic Shower Cartridge SAR00, Installation: Push Fit The SAR00 thermostatic cartridge is a fundamental component of a ENKI Winchester mixer shower valve. It can last a long time but it can show initial signs of wearing out after some years. Below are issues relevant to shower cartridges. Minerals, grit and dirt that flows with the water are filtered by the cartridge. Residue builds up in and around the cartridge clogging it. If this is the case, SAR00 shower cartridge replacement can return water flow to normal. Cartridges are equipped with O-rings to keep water from leaking. Abrasion, pinching, and years of using the shower valve will weaken the seals causing leaks. It may start small but eventually worsen if not immediately addressed. Another reason drips occur are cracks in the cartridge barrel allowing water to seep out. The mentioned issues can be resolved by replacing the seals or the cartridge. Shower mixers, or blending valves, combine hot and cold water to produce the water temperature demanded by the shower user. It is a thermostatic valve that takes hot water from a combination boiler or a hot water cylinder and mixes it with cold water. A lukewarm water temperature results from a 50/50 mix of hot and cold. Water pressure to the shower will fluctuate when someone at home opens the kitchen tap or flushes the toilet. The cartridge in the mixer shower will maintain a stable temperature in spite of the fluctuation.