Duel Mount Plate -Steel Metal Set Guitar Tuning Machines Value-priced Ping guitar machine with nickel plate and double-drilled posts for mounting in a solid or slotted headpiece The chrome-plated, standard metal buttons have been added to the open gear design Value-priced Ping guitar machine with nickel plate and double-drilled posts for mounting in a solid or slotted headpiece The chrome-plated, standard metal buttons have been added to the open gear design