The rubber contains air and has a certain shock absorption function, but it is not very wear-resistant and has not been widely used. Sticky rubber is characterized by good flexibility and very anti-slip. It is generally used on indoor sports shoes.

The carbon element is added to the common rubber material, which makes the rubber more tough and wear-resistant. Most running shoes use this kind of rubber, and the BRS letters are left on the back part of the sole of the running shoes to indicate that the carbon rubber is used in the outsole.