Being able to measure and adjust your MARTIN® Guitar's neck relief is a critical step in the setup process and will improve your playability and sound. MusicNomad is making it real easy for anyone to perform this task with our Measure and Adjust kits. The Precision Truss Rod Gauge comes equipped with the 3 most common relief measurements for Electric, Acoustic, Classical and Bass Guitars (.006”, .008”, .010”). For MARTIN®, use the .008" Gauge along with the clever Pick Capo and follow the instructions printed right on the gauge. When you are ready to adjust, MusicNomad's 5mm Premium Truss Rod Wrench is made custom to fit all models of MARTIN® Guitars truss rod nut that you adjust inside the soundhole except DSS-2018, OMSS-2019, Modern Deluxe Series. Our ergonomic handle and rubber protective bumper gives you the comfort around your prized instrument. Keep your Gauge close by as it works on any Guitar or Bass and the 5mm Wrench will work on other Guitar brands that require that size. Make sure you check out all MusicNomad's Precision Gauges and Tools used in the setup process. That's MusicNomad quality – raising the bar in equipment care.