Gotoh Midsize Gold 510 Tuners with Metal Knobs (3 per side) The SG510 series are recognized the world over as one of the top performing super tuners on the market These feature an 18:1 gear ratio They have evolved through improvement without any compromises along the way The come equipped with a considerable amount of high-technology as a standard With the improvement of precision fitting gears which give a marvelous touch on playing they have gained a considerable reputation and are trusted as the No.1 machine head by many musicians all over the world