APEC Ultimate super capacity pre-filter set is made in USA with high quality filtration components to provide a longer lasting filter set to protect and prolong the lifespan of your reverse osmosis system. Premium quality filter set lasts over 12 months for fewer filter change outs and high performance contaminant removal. These standard size filters are compatible with APEC RO-45, RO-90, RO-PH90, RO-PERM, RO-PUMP, RO-Hi, WFS-1000 and all other 10" standard size under counter reverse osmosis systems. APEC Ultimate super capacity pre-filter set is USA made and built to last 2x longer than other brands Includes (2) sediment and (4) carbon block filters to protect and extend the life of the RO system 1st stage 5 micron polypropylene sediment filter to remove dust, particles, and rust 2nd & 3rd stage extruded carbon block filters to remove chlorine, taste & odor High performance replacement filters are compatible with all standard sized under counter RO systems