Rubner Classical Guitar Tuning Machines-Gloss Hauser With Bearing Upgrade Special MoldFlon Anti-Friction Bearings Slow Molded Black PVC Buttons- Very Durable Black rollers, 16:1 Turning Ratio / 35-70 Roller Spacing Solid Brass- Set Weight 5.2 OZ 1 set (left and right), with matching screws