Natural stone with approx. 700 grains/cm2 to achieve a razor-sharp cutting edge on chisels, plane irons and other tools. Tools that require honing but have a rough or dented cutting edge should be treated with the coarse side of the combination stone 528-COM first, otherwise the surface of the 528-700 may be damaged.

Artificial combination stone with two grains for restoring and sharpening the cutting edge of chisels, plane irons etc.
A. coarse side with 120 grains/cm2, suitable for removal of dents in the cutting edge, to even or straighten out cutting surface, following the original pattern of the tool.
B. fine side with 400 grains/cm2, suitable for sharpening of cutting edges and smoothing of cutting surfaces.