Fitted to standard wood screws, these hand-assembled screwdriver sets feature nickel-plated steel ferrules and chromium- vanadium 8650 alloy steel tips with black oxide finish. Square handles are turned from quality hardwood and stamped with the size for quick recognition. Custom hollowground blades offer a precision fit and help prevent slipping under torque and damage to the screw heads or surrounding surfaces. Set includes seven drivers with heavy square shanks in the following dimensions (approx. blade width x approx. blade thickness): #2 - .145" x .020" (.368 x .051cm); #4 - .206" x .033" (.523 x .084cm); #6 - .235" x .040" (.597 x .102cm); #8 - .286&quo Mfg: Grace Usa