#5407 TRX 3.3 Engine, IPS shaft with recoil pull starter
For use in all Traxxas TRX 2.5 and TRX 3.3 equipped vehicles.
Pull starter can be removed to install the Traxxas EZ-Start system (sold separately). 

#5409 TRX 3.3 Engine, multi-shaft with recoil pull starter
Includes threaded crankshaft inserts for "short" and "standard" applications. Pull starter can be removed to install the Traxxas EZ-Start system (sold separately).

#5404 TRX 3.3 Engine, IPS shaft without starter
For use in all Traxxas TRX 2.5 and TRX 3.3 equipped vehicles with flywheel access. Requires use of an electric bump starter or starter box. Does not accept a pull start or the Traxxas EZ-Start system.            

#5406 TRX 3.3 Engine, multi-shaft without starter
Includes threaded crankshaft inserts for "short" and "standard" applications. Requires use of an electric bump starter or starter box. Does not accept a pull start or the Traxxas EZ-Start system.

#5270R EZ-Start 2 electric starting system
Includes EZ-Start controller, drive unit with high-torque motor, wiring harness, and mounting hardware. Requires a 7.2V battery pack (sold separately).