Features: Filter socks are the best form of mechanical filtration. This is an essential part for wet/dry filter systems, sumps, and diy filters. Removes excess food, detritus, organic wastes, and other particulates to lower ammonia levels and other undesirable substances. Used as mechanical filtration for any sumps and diy filters Specification: Micron rating: 150 micron (0.15mm) / 200 micron (0.2mm) Ring width:Approx 4 inches Length: Approx 15 inches Material: Polypropylene Color: White Quality: 1 Piece Package included:1x Aquarium Filter Socks