EDIT: updated with newer designa bumper arm for the 1/10 scale traxxas slash. the 2 holes in the middle of the part are for attaching an additional center brace for extra support.brace for mounting between the bumper armshttps://www.youmagine.com/designs/traxxas-slash-bumper-arm-bracerear bumper https://www.youmagine.com/designs/traxxas-slash-rear-bumper