Grover Sta-Tite 18:1 ratio horizontal/slotted peghead 3x3 tuning keys in nickel finish with ebony wood buttons. The classic open brass gear and fine 18:1 ratio makes this a favorite for both slotted peghead acoustic and retro electric guitars. Includes mounting screws. Requires 1/4"(6.35mm) holes for the tuning post. Mounting holes on each tuner are spaced 1"(25.4mm) apart. Features Grover's lifetime guarantee.