This inner tube is made of isobutylene isoprene rubber, which is better in air tightness, elastic damping and aging resistance than natural rubber.NOT recap, Totally Inflatable inner tube with 90 bent angle valve stem and a cap; WIDELY APPLICABLE:12.5x2.25 (12 1/2inchx2 1/4inch) Dirt Bike Replacement Inner Tubes product is simple to replace. Believe It doesn't take your much time to change the tire Colour:Black Material:rubber Size:12.5x2.25inch/30x5.7cm Package Contents: 2 * Inner Tubes 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.