This gear case may subject to break due to prolong usage or during collision / accident. This Tamiya (#50541) 4WD Touring & Rally Car Front Gear Case For TA01/TA02 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 and TA02 chassis.