The tool accurately checks the neck straightness & fretboard flatness independent of the frets.


The original design ensures that over 20 common guitar scales are catered for with this single tool - including Gibson, Fender, PRS & Gretsch.



The tool has two further original features:

1) Precision Straight Edge - 400mm Long. Useful for precision tasks including checking fret levels.

2) Removable Steady. This prevents the tool from toppling over, allowing it to remain safely positioned on the neck during setup and adjustments. (The steady can be used with or without strings fitted).



All scales from 24” to 27” (610mm-685mm) are catered for.

This includes the following common guitar scales:

24", 24.5", 24.5625", 24.625", 24.75", 24.84", 24.9", 25.0", 25.34", 25.4", 25.5", 26", 26.25", 26.5", 27", 630mm, 635mm, 640mm, 645mm, 650mm, 660mm & 670mm.


The design of the tool is based on checking the length of the fretboard that is capable of being deflected. The very highest frets are omitted since these are well beyond the heel/neck join and won't be affected by truss rod adjustment or string tension.


The tool has 18 notches and a double dot mark for position reference is provided. The positioning on the neck will vary depending on the scale of the instrument:

For shorter scales the dots are placed at the 11th fret.

For 24.5"-25.5" range, the dots are positioned at the 12th fret.

For longer scales the dots are placed at the 13th fret.


  • Universal design covers a wide range of scales.

  • Freestanding use with tool remaining in position, ensures easy observation of changes to neck when adjusting the truss rod.

  • Can be used for checking multiscale guitars.

  • Precision Straight Edge on one side.


24"-27" GUITAR SCALE NOTCHED STRAIGHT EDGE - With Precision Straight Edge