【High-quality materials】 The bottle cap is made of high-quality materials, and the winter caps on ground and ground pools in winter are corrosion-resistant and have good durability and stability. 【Easy installation】 Universal external threaded cap, threaded connection, easy to install and use, directly replace the old or broken one. 【Strong sealing】 This oil return cap is equipped with a rubber ring, which has strong sealing and will not damage the oil return pipe due to leaks. 【Fine Workmanship】This filter drain plug has fine workmanship, smooth surface, wear resistance, aging resistance, long service life, and can withstand extremely cold temperatures without slipping or shrinking. 【Multi-scene Use】This winter plug is suitable for swimming pool and spa accessories.