Material: The Boston inflatable valve made of high quality ABS material, strong and durable, corrosion resistant, not easy to leak air. Size: The underside diameter of Threaded part is 22mm (out)/ 20mm(inner). The specific size of Boston valve can be seen in the fifth picture. Please check size to make sure whether your valve bung fit this plug before purchase. Application: Great for standard Boston valves replacement kit and most of Rubber Dinghy Raft Kayak Pool Boat Airbeds, etc. The Valve is a one-way inflation valve, good for quick inflation. The air valve cap design is sealed ensures anti-leak inflation. Fit for the most of Intex boats/river run float, boston valve/jilong boats/ bestway airbeds/ decath and so on. Please check the size of your equipment before you purchase. Product Specification: Material: ABS Type: Inflatable Spiral Air Valve Plugs Color: Black Quantity: 2 Pcs Diameter of Thread Part: Approx. 20 mm / 0.86 inch Length of Thread Part: Approx. 17 mm / 0.67 inch Weight: Package List: 2PC *Replacement Air Valves