Features:Filter socks are the best form of mechanical filtration.High quality, durable and not easily damaged.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.This is an essential part for wet/dry filter systems, sumps, and diy filters. Specifications:Material: Nylon, PlasticSize: Diameter:10cm/3.94in, Length:25.5cm/ 10.04in, Width:13cm/5.12inColor: WhiteWeight: 20g Note:1.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid.2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package includes:1pc x Aquarium Filter Socks