Pool Antifreeze Plug: This winterproof rubber plug can protect your swimming pool pipes in winter and prevent water from entering and damaging the pipes by freezing. It can extend the life of swimming pool pipes and reduce defrosting problems. WIDE RANGE OF APPLICATIONS: Swimming pool expansion plugs are used as pipes, blocking oil skimmers, return pipes and detergent pipes, etc. Expansion plugs can also be used for pressure testing pool pipes or other leak detection methods, or to prevent water from flowing out during equipment maintenance. < p>HIGH-QUALITY MATERIALS: The rubber expansion plug is made of high-quality rubber and metal, with maximum stretchability to ensure tightness. It features compact size, corrosion resistance, rust resistance and long service life. EASY TO INSTALL: Our swimming pool antifreeze caps are medium in size and very easy and practical to install. It can be installed in seconds without any tools. It is a very practical swimming pool accessory. You will