Material: The Presta valve cores are made of zinc alloy, finely finished, waterproof, rust-resistant and have a long service life. Handy tools: The bicycle valve core accessories are small and handy. They replace old valve caps, keep air out of old valves, are oil-resistant and ensure good air tightness. You can easily take them with you on every ride and they don't take up too much space. So you no longer have to worry about your bicycle tires and can cycle with ease and comfort. Easy to use: This bicycle valve core replacement is easy to install and use. Simply use a wrench or valve core remover to screw in the Presta valve, one end for the Presta valve core and the small end for the Schrader valve core. All installation steps can be completed in just a few minutes without the use of any other tools. Wide range of applications: Our bicycle valve core set is suitable for Schrader/Presta/Presta Extender/inner tube valves, such as those of bicycles, motorcycles and cars. Essential accessories: The valve core is an essential accessory for bicycle tires, preventing air leakage and ensuring normal bicycle use. Durable, safe, and reliable. Should your bicycle's valve fail, it's essential to have spare parts on hand so you don't have to worry about accidents.