This 3-sided straightedge is made for checking fret height, or rather finding the one or two frets that are high or low. The edge lengths are calculated so that any one edge can bridge three frets. Designed to work on all standard guitar scales, including bass scales, it works with most others as well. The gauge is machined from 1/4” aluminum and is then black anodized. The longest edge is 3 3/8”.
