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 Resonator Guitars & Lap Steels.
The bone nut was easy to install. I sanded the length and depth with a table sander. The instructions are complete and easy to follow. Four zero frets of different sizes are included in the banjo kit--you try the smallest and work your way up until you have no open string buzz. Use medium viscosity cyanoacrylate (available from Stewmac) so you have time to set the nut and fret properly. I'm pleased with the results, improved tone, and hammer-ons and pull-offs are more defined.
Just got a second one. Used the first on a Tele build. The multiple heights included give plenty of options. Takes some tweaking but so does a standard nut and you don't have to worry about overdoing anything.
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.
$34.99