Good effect: protect your pool from the rigors of winter with antifreeze caps. A simple solution can prevent serious damage to your pool. Scope of application: used as pipe plugs, to plug skimmers, returns and cleaner lines, to prevent water from entering in pipes during the winter. Multipurpose: Expansion plugs also have other uses, such as pressure testing pool lines or other leak detection methods, or stopping the spread of pool water when repairs to equipment are made. Rubber Material: Rubber Pool Stoppers are made of rubber for maximum stretch to ensure a tight seal. Good Workmanship: Exquisite workmanship, beautiful appearance, small size and portable, giving you excellent using experience. Product Description < p>Scope of application: used as pipe plugs, to plug skimmers, returns and cleaner lines, to prevent water from entering pipes during winter. Expansion plugs also have other uses, such as pressure testing pool lines or other methods of leak detection, or stopping the spread of pool water when repairs to equipment are being made. Rubber material, Rubber pool stoppers are made of rubber for maximum stretch to ensure a tight seal. Good workmanship, Exquisite workmanship, beautiful appearance, small size and portable, providing you with excellent using experience.