Fret Slot Depth Gauge

Don't wait until after you've installed a fret to discover the slot wasn't quite deep enough! Dan Erlewine developed this remarkably handy “look-before-you-leap” gauge for quickly comparing the wire to the slot. Simply hold the flat edge against the fret tang, note the height of the tang against the reference lines, fit the appropriate curved edge into the slot, and compare the lines again.

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