The Katadyn Gemini (previously the CFS Chlorinex Filter System) is a two stage water filter designed to be permanently mounted under the sink. The Gemini consists of two stages of treatment in three phases. Phase 1 is a coarse filter which traps dirt and rust particles. Phase 2 (Stage 1) removes chlorine and other chemicals using an activated carbon element. Phase 3 (Stage 2) traps bacteria using the Katadyn 0.2 micro porous ceramic filter cartridge. This eliminates pathogenic bacteria.

The filter system is connected to the cold water system under the sink. The system has an infeed for unfiltered mains water and an outfeed for which the dechlorinated, filtered and purified water flows.

The service life of the activated carbon element is approximately 6 months and the service life of the ceramic element is 2-3 years. Both can be purchased separately from B&A Products.