Is your vintage tone machine drifting out of tune in the middle of the set? The Hipshot® Vintage Tuner Upgrade Kit is a risk-free step toward giving you consistent results from your beloved guitar. The Grip-Lock™ system securely clamps the string ends so that your pitch remains right where you set it. The 11/32” [8.5mm] tuning post shank and the UMP™ (Universal Mount Plate) allow the upgrade kit to install on your vintage guitar with no alterations to the headstock. At the drop of a hat, your old tuning machines can be reinstalled with no evidence that you ever upgraded.