Function: These expansion plugs are designed to winterize your swimming pool, safeguarding it from severe winter weather and potential staining damage. The tapered plugs, coated with rubber, can also be utilized to block or seal a variety of openings, including holes, pipes, drains, sinks, tanks, etc., in your pool, kitchen, bathroom, or yard. Used as pipe plugs, they effectively seal skimmers, returns, and cleaner lines to prevent water from entering the pipes during the winter months. Expansion plugs serve additional purposes, such as pressure testing pool lines or employing other leak detection methods, as well as halting water flow from the pool when equipment repairs are necessary. 100% Brand new and high quality. Material: Rubber + Stainless Steel Colour: Black Package 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 varying displays may cause the item's color in the picture to differ slightly from the actual product. The measurement allowable error is +/- 1-3cm.