Freeze protection and crack prevention for winter care - Our pool skimmer provides a freeze compensation function to protect the pool and prevent ice expansion from damaging the skimmer, helping prevent cracks in cold weather. Robust and durable - Made from high-quality ABS, this pool skimmer offers a solid construction that withstands harsh winter conditions and remains resistant to deformation and damage. Excellent compatibility - The skimmer closure fits 3.8 cm and 5.1 cm skimmer openings. It is suitable for large and deep skimmers and fits most in-ground skimmers. Easy installation - No water flushing is required in winter. Simply tighten the closure to secure, saving effort and time while keeping hoses dry. Use scenarios - Winterizing an in-ground pool in freezing climates to prevent skimmer damage from ice. - Upgrading to a reliable closure for pools with large or deep skimmers to improve fit and protection. - Quick, hassle-free winter maintenance for pools with standard skimmer setups, helping save time and maintenance steps.