TDR Gearbox Ratio 4th Gear for Jupiter Z1 / Vega ZR

Advantages of TDR Gear Box Ratio : 
- Made with special material processed using high technology machine which produce more precise gear box ratio so that easier to do gear shifting.
- Designed with special heat treatment guarantee that gear ratio have better durability.
- Available in many size adjustable as engine needs and track character.
- TDR Gear Ratio has been used by many racing team.