Watts Kwik-Change™ Cartridges 2 pack
WQCSC-11 high performance 5 micron pre sediment filter,
WQCCC-11 High performance 1 Micron carbon block filter cartridge which removes chlorine Bad tastes and Odor from the water prior to the RO Membrane
These are the 2 pre filters prior to the membrane, (3rd filter) regular changing of these 2 filters will prolong the life of the TFC Membrane.
The Full range of Watts cartridges codes are , Cartridges codes WQCSC-11, WQCCC-11,WQCM-11, WQCGAC-11, Watts quick change cartridges