The Planet Waves Auto-Trim Tuner is a precision designed tuning machine with built-in hardened steel string cutters and individual string clamps. The patent-pending design cuts excess string while tuning guitar, eliminating need for extra tools for cutting excess string. Individual string clamps securely hold string in tuner, so there is no need to for multiple wraps around the tuning post. Auto-Trims rugged die cast outer casing houses precision machined 18:1 bevel and worm gears, providing smooth, exact tuning, while virtually eliminating backlash and slippage. The string clamp and cutting mechanism makes the chore of restringing a snap. A Ned Steinberger design.Patent-pending design cuts excess string while guitar is tuned, eliminating need for extra string-cutting tools.Individual string clamps securely hold string in tuner ? no need for multiple wraps around the tuning post.Excellent for aggressive tremolo use.Precision 18:1 gear ratio provides smooth, exact tuning, while virtually eliminating backlash and slippage.