This Everpure EV9534-12 EC110 prefilter cartridge filters out larger dirt and rust particles, extends the life of primary filter cartridges. The prefilter cartridge fits most 20" drop-in housings. It's durable slim bowl design makes cartridge change outs easy to handle.. The EverPure EV9534-12 EC110 filter's sanitary cartridge replacement is simple, quick, and clean. Oxidizing water filter for iron and sulfur in low water volume applications makes this filter safe. It's Tightly spun EC110 sediment cartridge delivers 10 micron nominal filtration.