Material: The winter expansion plugs are made of high quality rubber material, with stainless steel screw bolts, reliable, stable, anti rust, not easy to break, durable and long lasting. Function: Pool Winterizing Plug is designed to plug your swimming pool pipes after they have been drained, avoiding water entering and causing freeze. Easy to Use: Just screw the plugs into all return and drain inlets, convenient to handle and use, need no much efforts. Application: Used as pipe plugs, to plug skimmers, returns and cleaner lines to prevent water from entering the pipes during winter. Multifunction: The plug can also be used for pressure testing pool lines or other methods of leaking detection, or stopping water from the pool. Specification: Material: Rubber Color: Black Type: Expansion Plug Size Chart: 25cm/9.84inch 38cm/14.96inch 51mm/2.01inch 63mm/2.48inch Package Includes: 1 Piece Expansion Plug Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful online shopping! Customer satisfaction is our primary concern. If the product is somehow cracked or broken during shipping, please feel free to contact us. We will try our best to give you a satisfactory solution.