Estone New Chrome Locking Guitar Tuners Pegs tuning Machine Heads 3R3L Guitar Set Set of 6 quality black machine heads for steel string (electric or acoustic) guitars (3L + 3R) Now you have no more worries as to how have to pack for the handling guitar, piano small knock a small touch button and let the strings out of tune! The guitar will not off key if you lock the screw post when tune the guitar properly. Quality sealed machine heads Auto Locking Tuners (Tuning Pegs) Heavy duty internal gear