Feature: 1. Manufacturing Material: Bicycle inner tubes are made of high quality butyl rubber material, it is durable and strong, which undoubtedly extends service life. 2. Multiple Advantages: It has the advantages of better sealing performance, ozone resistance, aging resistance, shock absorption and electrical insulation. 3. Comfortable and Safe Riding: Butyl rubber inner tubes absorb the impact of bumpy roads, making the ride more comfortable and safe. 4. Simple Operation: Installation is quick and easy. Use a wrecking bar to pry open the outer tube, remove the old inner tube, align the air nozzle of the new inner tube with the air nozzle of the steel circle, place the inner tube, inflate it, and arrange the outer tube to complete the operation. 5. Ideal Replacement: Heat resistant and withstand the wear and tear of daily use, this is undoubtedly the ideal replacement for broken inner tubes of bicycles. 6. Product Size: The tire optional sizes are 14in, 16in, 18in, 20in, 22in, 24in, 26in and tire width is 1.75‑2.125in. Specification: Item Type: Bike Inner Tube Material: Butyl Rubber Air Nozzle Model: For Schrader ValveTire Width: Approx.1.75‑2.125in . Package List: 2 x Inner Tube 2 x Wrecking Bar Note: Before replacing the inner tube, check for any stones or incisive objects that might damage the inner tube left in the tyre, and clean it if so. When replacing a bicycle inner tube, be sure to add a small amount of air to the inner tube before installation. This gives it shape, so it doesn't contort or clump together, which could cause clamping.