Graph Tech PQ-1578-00. This a great option to upgrade or replace the nut on your 12 string guitar.  It is pre-slotted to make for a quick and simple install.   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. Please note that all Graph Tech nuts are slightly long and wide to ensure extra room to achieve a perfect fit for your guitar. This extra material can easily removed with fine grit sandpaper.