Premium ABS MaterialThese boston air valve is made of thicken ABS material, durable, odorless, lightweight, portable, anti-rust, anti-corrosion and not easy to age, can be used for a long time. Anti-leakage DesignThe bottom of our spiral air plugs has an air cushion design to prevent air leakage, which can be perfectly fitted to prevent air leakage. Provide strong protection for your safety. Ideal Valve ReplacementThe anti-leakage air valve bungs is an ideal & economical choice for replace the air valve. The size of the screw plug mouth is 20mm \/ 0.78, please confirm the size before purchase. Quickly Inflate & DeflateEasy to use, you can inflate and deflate quickly (one-way inflation) just by placing the inflatable boat air valve on the inflation port, providing you with a convenient life. Wide ApplicationThe boston spiral air plugs are suitable for most rubber dinghy, hot tub, airbeds, inflatable boat, raft, etc. The boston air valve is a essential accessories for water lovers Product description Features 1. These boston air valve Fits 20mm\/0.78 inch hole. Suitable for most rubber dinghy, hot tub, airbeds, inflatable boat, raft, etc. 2. Made of thicken ABS material, durable, odorless, lightweight, portable, anti-rust, anti-corrosion and not easy to age, can be used for a long time. 3. Designed with anti-leakage air cushion, the spiral air plugs can be perfectly fitted to prevent air leakage. Provide strong protection for your safety