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 the spiral air plugs features an air cushion design to prevent air leakage, providing a secure fit and reliable airtight performance. Offers strong protection for safety. Ideal Valve Replacement These anti-leakage air valve bungs are an ideal economical choice for replacing standard air valves. The screw plug opening measures 20–22 mm; please confirm compatibility before purchase. Quick Inflate and Deflate Easy to use for fast inflation and deflation (one-way inflation). Simply attach the inflatable boat air valve to the inflation port for convenient operation. Wide Application These Boston spiral air plugs are suitable for most rubber dinghies, hot tubs, airbeds, inflatable boats, rafts, and other inflatable products. An essential accessory for water sports enthusiasts.