This Luthier's Digital Caliper has a custom jaw notch for accurately measuring fretwire crown height (the height above the fretboard). This is essential for comparing new wire to original wire. And there's a notch on the depth gauge to measure fret height on the instrument.
Handy for lots of other measuring jobs in the shop - nuts, saddles, tuners, tool setups and more - this caliper has long-life stainless steel jaws. Featuring LCD digital readouts in inches or millimeters, it measures outside, inside and depth dimensions up to 6" (154mm), with super-accurate .0005" (.01mm) resolution. The jaws can be locked at any position.