This tailpiece is designed to screw down directly to a flat top solid body guitar. The string ball fits neatly and securely into the keyhole shaped opening locking into place with string tension. This shorter variant was designed to increase the break angle from the bridge using 1/4 inch height instead of 3/8 inch like it’s taller counterpart. Originally designed for a famous guitarist who was quite Grateful for the tone the milled brass added to his instrument! Super easy three screw installation for surface mounting stop tailpiece instruments.