[Quality Material] This kayak air valve is made of environmentally friendly high-quality material, which is waterproof and wear-resistant. [Double Seal] This boat air valve core and cover both have sealing rubber rings. Double sealing effectively prevents air leakage. Please check if the size of your kayak valve fits this plug before purchasing. [Two Methods] This boat valve has two inflating methods. One is to inflate when the spring in the middle of the valve is not extended (inhalation only, no air out). The other is to rotate the operating lever in the middle of the valve to fully open it (inlet and outlet). Regardless of the method used, always tighten the air nozzle cover and air nozzle after inflation to prevent air leakage. [Application] This air gas valve replacement consists of three parts: inner part, outer part, and valve cover. The upper outer diameter is approximately 2.5 inches (6.5 cm), and the lower outer diameter is approximately 1.6 inches (4.2 cm), suitable for most inflatable boats, river rafts, and kayaks. Features: Includes one inside part, one outside part, and one valve cap. Fits most inflatable boats, river rafts, and kayaks. Easy to inflate and deflate. Double seal leak protection. Excellent air retention performance. Great accessory for boating enthusiasts. Specifications: Upper Outer Diameter: 6.5 cm / 2.5 inches Lower Outer Diameter: 4.2 cm / 1.6 inches Height: 5 cm How to Use: Method 1: Inflate when the spring in the middle of the valve is not extended (inhalation only, no air out). Advantages: After inflation, remove the inflation tubethe air nozzle automatically closes with no air leakage. Disadvantages: Slower inflation speed, longer inflation time, possible abnormal noise due to gas pressure. Method 2: Rotate the operating lever in the middle of the air valve to fully open it (inlet and outlet). Advantages: Faster inflation speed, shorter inflation time, no abnormal noise. Disadvantages: After full inflation, when the inflation tube is removed, some air may escape because the valve remains fully open until the operating lever is manually rotated to close it. In both cases, after inflation, ensure the air nozzle cap and air nozzle are tightly screwed to prevent air leakage. Color: Gray Material: Plastic Package Contents: 2 x Air mattress valves Note: Light reflection and different display settings may cause slight color variations between the image and the actual item. Measurement error allowance is +/- 13 cm.