The 39T option provides slightly taller gearing

The aluminum construction provides improved durability while keeping the hitch lightweight

Heavy-Duty aluminum links

1/8 and 1/5-scale shocks

Traxxas 10856X Aluminum Center Driveshaft RC10 Parts The 39T option provides slightlyTraxxas 10856X Aluminum Center Driveshaft Upgrade your drivetrain with this genuine Traxxas aluminum center driveshaft. Machined aluminum construction adds strength and durability over the stock plastic driveshaft, helping transfer power reliably between the front and rear drivetrain under hard use. Genuine Traxxas option part Aluminum center driveshaft Upgraded aluminum construction Direct fit installation