Wide Front Bumper, Black: ST 4X4 by RPM. $8.83. RPM Wide Front Bumper Black for Traxxas Stampede 4x4. #81042 Notes: RPM Wide Front Bumpers for the Traxxas Stampede 4x4 are stock replacement parts. Simply remove the stock front skid plate, replace it with the RPM version and you're ready to go. It even incorporates the mounting points for the stock upper bumper, if you wish to keep it in place.