This is an end cap for the Makita track saw rail. It slips on and is held by the foam on the bottom of the rail being squeezed. It has a slot so you can still install a clamp. It is printed in two parts so it won't need any supports. Sim[ply glue the two halves together using crazy glue or the adhesive of your choice. It allows the power cord and vacuum hose to easily slide over the end of the rail with no binding.