Fender Pure Vintage String Tree Kit

This kit includes a string tree plus spacers. It can be used without a spacer, screwed right down to the face of the headstock using the shorter screw. Or you can use one of the two included spacers under the tree to raise it from the headstock face, using the longer screw. There are two spacers included, a nylon one and a metal one, as used by Fender at different periods in their history.

Making a Strat with a tremolo stay in tune is largely about minimizing friction in the strings' path. There are several culprits, and the string tree(s) is perhaps the biggest offender. Forcing the B & E strings to angle sharply down from the nut, pass under the string tree, and then angle sharply back up to the tuner post adds a lot of friction, and this is very problematic in terms of causing tuning instability.

The string tree doesn't need to exert much downforce. If you were to remove the string tree, you'd usually find that the B & E strings ring in the nut slots when played open - it produces a sound similar to a sitar. This goes away as soon as you fret the string, the ringing only occurs on the open strings. But if the merest amount of pressure is applied to the strings in the area where the string tree is installed, the ringing is muted.

This spacer has the effect of raising the string tree so that it exerts much less downforce on the open strings. There's still plenty of downforce to stop the ringing, but the friction is greatly reduced, and tuning stability is improved.