7-Stage Reverse Osmosis Replacement Filters (7QCRO) - Filters #1, 2 & 3This 3 pack of filters #1, 2 & 3 are the primary replacement filters which are guaranteed to last a minimum of 1 year or longer (We recommend replacing these filters ever 1 2 years on average). Further details on consumption are listed on each individual filter. The included filters are: Stage 1: Sediment Filter Reduces suspended particles in the water such as dirt or sediments Stage 2: Granular Activated Carbon Filter Reduces chlorine, chloramines,