This gear may subject to wear and tear due to prolong usage. This Tamiya (#53127) Skyline Speed-Tuned Gear Set TA02 Chassis is a good replacement spare parts. I have bought 2 new sets from RCMART to help my friend to restore his TA01 chassis. Thanks RCMART for good service and reasonable price. I recommend this part to someone who needs to restore old TA01 chassis.