Features 1、High quality aluminum alloy material, durable, sturdy and has a long service life. 2、The silicone material has significant rust and corrosion resistance, and is strong and durable. 3、Enlarged base, high air density, good sealing, quality assurance, no air leakage. 4、Suitable for most mountain bike, strong practicability and high performance. 5、Compact size, small and lightweight, easy to carry, does not take up space, reliable body. Item Type: Tubeless Valve Stem Material: Aluminum Alloy + Silicone Length: Approx. 40mm/1.6in Valve Core Diameter: Approx. 5.75mm/0.2in Base Diameter: Approx. 12.80mm/0.5in Weight: Approx. 11.0g/0.4oz Quantity: 1Pair Specification: F/V Presta Valve Application: Tubeless tires for road bikes and mountain bikes How to use: 1. Check whether the valve core is tightened. 2. Remove the lock nut and O-ring. 3. Insert the valve stem into the valve hole on the rim. 4. Place the O-ring on the stem. 5. Screw the lock nut onto the valve stem. 6. Tighten the lock nut until the rubber end of the valve is tightly pulled into the rim hole. Package List 1 Pair x Tubeless Valve Stem 1 Pair x Nut