Hosco H-GB4 Groobar Set, Groobar Set, 4 non-hardened steel gauges in different thicknesses, Protection against too deep cutting of the string notches in the saddle, Blade thickness L: 1.07 mm / 0.042"", Blade thickness L 1.27 mm / 0.050"", Blade thickness M 1,42 mm / 0,056"", Blade thickness H 1.65 mm / 0.065""