Model M644-00 Nut Slotted Slanted Bottom L44.32mm (Select Material)

The radius of the precut slots are not a match for my Martin D-18. When sizing the nut, when I got the clearance perfect on low and high E strings above the first fret, the rest of the strings are too high, especially D and G strings. I can't go any lower on the nut without getting buzz on the E strings so I will need to buy tools to cut down the grooves so the radius of the precut slots in the nut matches the radius of the guitar neck. Perhaps most modern acoustic guitars have more curvature on the fretboard.

Also, the slots are just slightly too close together--I carefully measured and looked for a nut on your site that was closer to what I had before, but could not find a closer match. This one is close, but compared to my other Martin D-18, the playability, especially in first position is just not as good. Guess I need to learn to cut my own nut from a blank next time. There isn't a luthier anywhere within hours of me that I trust to create the nut and set up this guitar, and I'm quite picky about playability as a pro and was so hopeful graphtech would have what I needed but I guess most Martin acoustic players don't buy graphtech nuts.

However, when I bend strings, they do return to proper tuning better than with my old bone nut, so the XL self lubricating feature works as advertised.