Feb 08, 2022 · The dual thumbscrew SoftGrip Clamp was designed specifically for those looking for an easier to use clamp, that would also prevent scratching on coated or highly polished blades. Not for use on blades 1/2" wide or less. For sharpening blades 1/2" wide or less (such as tiny swiss armytype blades), use the Standard Knife Clamp.