Sediment Water Filter Cartridge by Ronaqua 10"x 2.5", Four Layers of Filtration, Removes Sand, Dirt, Silt, Rust, made from Polypropylene (50 Pack, 5 Microns)Industry Standard 10 inch 5 Micron Sediment Filter Used for effectively removing most sediments, cysts, chlorine, and fluorides This is a filter for a standard Reverse Osmosis Water Filtration Unit or any type of Water Filtration Unit with a 10 inch housing Product Lifetime: Replace two or three times a year depending on your water quality This filter is wrapped and sealed and meets NSF (National Science Foundation) Standards and Regulations