(Set of 4) Hipshot HB10 American Classic tuners for bass guitar. Nickel finish with clover key. Right handed 4 inline. The finest quality materials and precision engineering have been combined to make American Classics the best bass tuning machines you can buy. 27:1 ratio with adjustable gear lash tension. Fits most Fender Japan Mustang Bass® and Japan Aerodyne Bass®(models with small key) and other applications with 9/16"(15mm) peghead holes. Mounting hole spacing on each tuner plate is 7/8"(22mm) across the top, 15/16"(23mm) across the bottom, and 1-3/8"(35.5mm) top to bottom(on center). Includes bushings and mounting screws. Includes bushings and mounting hardware. Made in the