GraphTech PQM64400 TUSQ Acoustic Guitar Nut, Slotted, Martin Style, 1 3/4-Inch Length TUSQ delivers a rich tone, crystal clear bell like high end with big open lows and a significant increase in harmonic content and harmonic sustain Increase harmonics equals more richness and character in your tone Its the difference between a four piece choir and a twelve piece choir singing every time your play a note