This is a versatile tool originally designed by Hosco. It provides six most common fretboard radiuses measurement and also you can check the height fret crown and string action with it.
- 6 radiuses : 7-1/4″, 9-1/2″, 10″, 12″, 14″, 16″
- Gauging fret crown height (0.1mm – 1.5mm)
- Gauging string action
- 210mm x 25mm
- It is light and the thickness is <1mm.
Fret crown height gauging (mm/10)
String action gauging
String action : 2.5mm
Fret crown height (high fret) ex. 1+10=11, 11/10=1.1mm
Fret crown height (low fret) ex. 0+10=10, 10/10=1.0mm