"Upgrade your bike's performance with our 2 Packs Bike Vacuum Tire Presta Valve Nut set. Each pack contains 2 nuts and 2 sealing rings, offering a complete solution for easy replacement. Made from high - grade aluminum alloy, these lightweight presta valve nuts minimize impact on wheel balance, ensuring a smoother ride on both mountain and road bikes. Their versatility shines as they're compatible with various bike types, from city leisure bikes to folding ones. The unique sealed O - rings play a dual role. They enhance airtightness, keeping your tires optimally inflated, and prevent the nuts from loosening, protecting your wheel hubs. Installation is a breeze - just place the sealing ring first, then tighten the nut. Get this essential cycling part and enjoy a more reliable and efficient ride. "