The GrooveTech Sound Hole Truss Rod Driver allows you to make swift, accurate truss rod adjustments for your acoustic guitar, even if the nut is hidden inside the sound hole. Rather than make it easy for guitarists, manufacturers often make truss rod adjustment difficult. This professional-grade tool has a long right-angle shaft with a precision ball-end tip, plus long blade segments and an oversized handle for superior control. Own a lifetime of quality instrument care with GrooveTech Tools, designed to last and easy to use for players of all levels.