The Zero Glide Replacement Nut System borrows the "zero fret" concept to reduce string contact in the nut by up to 93%, increasing tuning stability, playability, and open string tone. It only takes a few minutes to install with absolutely no permanent alteration to your instrument. For Classical Guitar (Blank).
See the Classical Guitar DelCamp review of the Classical Zero Glide nut.
Also available in Black Delrin.
I bought the mandolin version and fitted it to my Gibson. There's a lot of extra material to remove, but the result was great. Easier tuning (the old nut had tight slots for the A strings), better intonation. Later I used one of the extra frets in the package to fix a tenor guitar. For that, I simply filed the necessary ledges in the existing nut and widened the string slots. It would be nice if Stew-Mac would also sell the offset tang frets separately, for retrofitting to an existing nut.
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