The TonePros SS1 Imperial Locking Tailpiece Posts and Bushings have a threaded cap that screws into the stud tightening down on to the top of the tailpiece or wraparound bridge and locking it to the post from above, this ensures the wraparound does not lean on the posts and provides a more solid connection with the guitar body, ensuring maximum sound transmission and sustain. The locking studs also keep the tailpiece in place during restringing so it cannot accidentally fall off, potentially becoming damaged or damaging the guitar top. The imperial brass studs have the standard 5/16-24 thread used on Gibson USA and PRS Core guitars.