Usage Tips:Function: These expansion plugs are to winterize your swimming pool, protecting it from harsh winter and stain damage. The tapered plugs, covered by rubber, can also be used to block or seal some holes, pipes, drains, sinks, tanks, etc. in your pool, kitchen, bathroom or yard.Used as pipe plugs, to plug skimmers, returns and cleaner lines - to prevent water from entering the pipes during winter.Expansion plugs have other uses too, such as pressure testing pool lines or other methods of leak detection, or stopping water flow from the pool when equipment repairs are made100% BandMaterial: Rubber + Stainless Steelcolour: BlackPackage Contents:6 x Pool Plug(2 x 25mm, 2 x 38mm, 2 x 51mm)Only the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.