Our Next-Generation HiFlux RO membranes offer all of the benefits of traditional RO membranes but waste far less water (waste:product ratio of 1:1 instead of 4:1) and offer high capacity for equivalent size. This filter set can be used to upgrade any standard 1812 size RO system (with a 50GPD or 75GPD membrane) Replacement filter set for 5-Stage RO system. This set should be replaced every 24-months. Includes: - 5-micron Melt Blown Sediment Filter (2.5 x10" cartridge size) - Granular Activated Carbon Filter (2.5 x10" cartridge size) - 5-micron Carbon Block Filter (2.5 x10" cartridge size) - In-line Taste & Odour Filter (2x10" inline filter size) - 280GPD HiFlux RO membrane (2012 membrane size, compatible with 1812 housings)