These are rubber tire inserts designed to fit 24mm wheels with 24mm width rubber tires. They come in pairs and the green color easily identifies the insert as a medium firmness.
- Medium molded tire inserts provide a more neutral alternative compared to hard and soft inserts.
Note: The firmer the insert the less traction your tire will yield. The softer the insert the more traction you will get out of your tires, but they will also wear out faster. | 
