The Cold Water Filter has been designed to allow you to quickly switch from tap water to cold filtered water. Any Quooker-tap will now be able to supply cold filtered water via a single push and turn which when engaged will light the tap ring blue. The water passes through an activated-carbon filter which ensures the water tastes and smells better. The filter is easy to replace and must be changed at six monthly intervals. This includes filter cartridge. Please note this accsessory does not include tap.