Introducing the Music City Bridge “Nut Slot Gauge.” This simple and effective tool ensures you achieve the lowest possible nut action while eliminating open-string buzz. 

With four built-in preferences of bump up above a "zero" fret - 0.000 (in thousandths of inches), 0.003, 0.005, and 0.008, the Nut Slot Gauge easily and accurately measures your nut slots' current height, with or without strings, and unaffected by action or the truss rod setting. This helps you achieve the softest feel and also the least detuning due to grip.

How to use the Nut Slot Gauge:

1. Move the string out of the slot.
2. Place the measuring gauge into the slot and slide the tool toward the bridge.
3. If you hear a click, then the nut is taller than the gauge.
4. If you don't, the nut is lower than the gauge.

"The nut slot height is one of the most critical and routinely neglected aspects of a great guitar setup. It is difficult to control the depth within the tight tolerances that are required.  You work the slot down slowly until it’s just right, but if you go too far the string buzzes and you have to start again!  The Music City Bridge “Nut Slot Gauge” provides the instant and dependable working feedback necessary to control and refine slot depth and deliver a top-notch nut setup every time."

- Ned Steinberger