eBay

Curved 12" Radius 42mm Bone Nut for Fender Stratocaster, some Allparts Necks etc

New curved bottom pre-slotted bone nut
String slots are nicely cut, eliminating a lot of unnecessary slot filing
Compatible with some Fender Deluxe Guitars, some Allparts necks, and other 12" radius necks with curved nut slot.
Dimensions Approx: 42mm long, 3.4mm wide. Approx height: 5.3mm low E, 4.8mm high e.
E to E string spacing Approx: 33.5 to 34mm
Picture is one of the actual nuts being sold, not generic

.................................................................................................................

Please note: pre-shaped nuts are not generally drop-in replacement. In most cases some sanding or shimming may be necessary to fit the width and height of your guitar slot properly. If you need to lower the overall height or fine tune the bottom contour to your specific guitar, just lay out a strip of sandpaper between 2 frets, carefully and evenly move the nut back and forth removing some material until desired height or shape is achieved. If need to lessen the width, use the same method on a flat surface. Some minor slot filing may be required as well.

Do I need a flat bottom or curved bottom nut?

Most, if not all Fender Squire, and other Strat and Tele style guitars made oversees (China, Indonesia, etc.) use flat bottom nuts.
This nut cannot be used as a replacement for a flat bottom nut.
In most cases, Fender’s made in the US and Mexico use curved bottom nuts ranging from 7.25” to 12” radius, with 9.5” radius being very popular found on many American and MIM standards.

Do I need 42mm or 43mm?

That could depend on your guitar or your preference. Guitar specs usually include nut width (see Fender website for example). Sometimes specs can differ slightly from what is actually on the guitar. The difference between 42mm and 43mm is very slight (42mm is approximately 1.65” or 1 5/8”— 43mm is approximately 1.69” or 1 11/16”). Many Fenders, Squire, and other Fender style guitars spec 42mm nut. Some use 43mm or (42.8). For an exact replacement, it’s best to measure your present nut or go with what is spec’d. Some prefer a 43mm nut regardless, because 43mm sometimes gives slightly wider string spacing, and/or the opportunity to sand the ends of the nut to precise width of the neck…or not.