Rusco 3/4-140-F 140 Mesh 3/4 Spin-Down Polyester Filter with Flush Valve The Rusco clear cover is made of high impact polymer resin for maximum strength and durability. The The Rusco sediment filters use centrifugal separation technology to filter sediment from water. The Rusco filtration system has a polyester screen filter. The Rusco filter system&apos;s filter screen is cleanable and reusable. The Rusco systems have a clear cover that can easily be removed for cleaning.