Tire tube replacement: The bike tube is made from premium butyl rubber. It features better sealing performance, , anti-aging, shock absorption and electrical insulation merits. Easy to install: Installation is quick and easy.Please follow inflation guide when airing a tire from a complete flat. Hassle free to replace your old tire tubes within minutes which is time saving and efficient. Please kindly confirm the size of your bicycle tire before you buy. Remember to always add a little air (to give the tube form) to the new inner tube before installing. This will prevent it from bunching up and/or causing a pinch flat or possibly blowing the tire off the rim (when you immediately and fully inflate) which ultimately will the tube. size: 60mm Material: Butyl rubber colour: black Package Contents: 2 x bicycle inner tube Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Tire tube replacement: The bike tube is made from premium butyl rubber. It features better sealing performance, , anti-aging, shock absorption and electrical insulation merits. Remember to always add a little air (to give the tube form) to the new inner tube before installing. This will prevent it from bunching up and/or causing a pinch flat or possibly blowing the tire off the rim (when you immediately and fully inflate) which ultimately will the tube. Easy to install: Installation is quick and easy.Please follow inflation guide when airing a tire from a complete flat. Hassle free to replace your old tire tubes within minutes which is time saving and efficient. Please kindly confirm the size of your bicycle tire before you buy.