Protect your body shell from body pin scratches and enable a much better sit for your shell. Ideally for use with 1.10 car shells however can be used with 1.8s by widening the center hole. Simply measure the body post is a minimum 3mm in diameter. It will be loose at this size so ideally 3.6mm minimum is much better. Not recommended for posts any larger than 6.5mm. Note the center hole or bore will need widening. 4mm thick x 20.72mm wide. 3.58mm center hole which can easily be widened for thicker body posts.