[SIZE]32mm (Regular valves). Fits all 20inch x 3.0inch tires & tubes [Installation Precautions] check the side of your tire for the tire size your bike uses [MORE DURABLE] The bike tube is made from premium butyl rubber. It features better sealing performance, resistant, anti-aging, shock absorption and electrical insulation merits. [Easy To Install]Installation is quick and easy. 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. Install]Installation is quick and easy. 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. [Safe Bike Tires] The butyl rubber tire tube replacement absorbs shocks on bump road for a comfort and safe . It is heat resistant and stands wear and tear for daily use. Colour:black Material:Butyl rubber Package Contents: 2x 20 inch bike tubes Only the above package content, other products are not included. Note: Light 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.