This filter sock is good for improving water quality and protecting the water system and is widely used in fountains, fish tanks, gardening, water feature, fishing filtering. Specification Color: White Material: Polypropylene PP Diameter: 10.5cm / 4'' Overall Dimension: 38 x 14cm / 15 x 5.5'' (L*W) Package Content: 2 x Filter Sock Advantages Made 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. Instruction Easy to use: put the filter sock on the skimmer basket, easy to filter most of the stuff. Notice Please kindly note that there will be a 1-2cm tolerance of measurement.