Features1. Material: The winter expansion plug is made of high-quality rubber material and stainless steel screws, which are reliable, stable, rust-resistant, not easy to break, and durable.2. Function: The design purpose of the anti-freeze plug in the pool is to block the pool's pipeline after draining, preventing water from entering and causing ice formation.3. Easy to use: Simply screw the plug into all return and drain ports, making it easy to use and operate without too much effort.4. Application: Used as a pipe plug to block skimmers, return pipes, and cleaning pipes to prevent water from entering the pipes during winter.5. Multifunctional: This plug can also be used for pressure testing of pool pipelines or other leak detection methods, or to prevent pool water from flowing out.SpecificationMaterial: RubberPlug size: 25 mm, 32 mm, 38 mm, 45 mm, 51 mm, 63 mmColor: BlackSize: 4 x 3 x 3 cm, 4 x 4 x 3 cm, 5 x 4 x 3 cm, 6 x 4 x 4 cm, 6 x 5 x 4 cm, 7 x 6 x 5 cmWeight: 31 g, 48 g, 65 g, 83 g, 100 g, 120 gPackage includes:1x Expansion Plug