The D'Addario 3 + 3 format Auto Trim Tuning Machines are precision tuners that automatically cut the excess string while changing strings, eliminating the need for string cutting tools and making string changes easy and fast. The 18:1 ratio worm gear construction ensures greater precision than standard tuners and ensure tuning stability even during the hardest playing. Includes 6 tuners and mounting hardware. Chrome finish. 3 + 3 design for instruments that have 3 tuning machines on each side of the headstock.