The Aqualisa Thermostatic Shower Cartridge Assembly, Manufacturer Code 022801 is applicable for gravity-fed showers/water systems. This product includes gasket/filter and screws. This Aqualisa Thermostatic Shower Cartridge Assembly is a genuine, brand new Aqualisa product. It uses Aqualisa patented bi-metallic coil to precisely control the temperature of your shower. This is the most universal cartridge and it can be used on all water systems. Built in fail safe - should one water supply become blocked, the shower shuts down. Please note with Combi Boilers a cold water regulator must be fitted into the valve body during installation. This is a replacement thermostatic cartridge for the Classic 200 and Aquavalve 600 Aqualisa showers.