Premium ABS Material: These Boston air valves are made of thickened ABS material, durable, odorless, lightweight, portable, anti-rust, anti-corrosion, and resistant to aging, ensuring long-term use. Anti-leakage Design: The bottom of our spiral air plugs features an air cushion design to prevent air leakage, providing a secure fit and reliable protection for your safety. Ideal Valve Replacement: These anti-leakage air valve bungs are an ideal economical choice for replacing air valves. The screw plug opening measures 20-22 mm; please confirm the size before purchase. Quickly Inflate and Deflate: Easy to use, allowing for quick inflation and deflation (one-way inflation) by simply attaching the inflatable boat air valve to the inflation port, offering added convenience. Wide Application: The Boston spiral air plugs are suitable for most rubber dinghies, hot tubs, airbeds, inflatable boats, rafts, and more. This Boston air valve is an essential accessory for water enthusiasts!