Rear Bumpers for the TTraxxas Rustler require a bumper mount (either a TTraxxas 3677, RPM#80902 or RPM#80905 not included) or a Wheelie Bar (TTraxxas #3678 not included) to install.
If your version did not come with a bumper mount or wheelie bar, you will need to acquire one prior to installing. Works with most known TTraxxas Rustler bodies. Aftermarket or non-standard bodies may require trimming for proper fit