This filter sock is good for improving water quality and protecting the water system and is widely used in fountains, fish tanks, gardening, water features, and fishing filtering.SpecificationMaterial: Polypropylene PPDiameter: 15cm / 5.91"Overall Dimension: 52cm / 20.47"Package Content: 3 x Filter SocksAdvantagesMade of sturdy material with good workmanship, solid construction, and a delicate sewing process, it is lightweight and soft, reusable and durable, easy to clean, and pressure and impact-resistant.InstructionEasy to use: put the filter sock on the skimmer basket, easy to filter most of the stuff.NoticePlease kindly note that there will be a 1-2cm tolerance of measurement.