Because Spyderco's bench stones are flat and broad they are highly effective for honing wide tools like plane irons, chisels, large blades, woodworking equipment, even ski edges.
After many requests, Spyderco is now manufacturing an ultrafine-grit 2" x 8" x 1/2" bench stone. Ultrafine stones are ideal for professional polishing and finishing and can tighten the steel's scratch pattern bringing an already sharp edge to an even keener level. The stone comes packaged in a rigid polymer black storage case complete with non-skid rubber feet for tabletop use. As with all of Spyderco's ceramic stones, use our benchstones dry without lubricants or oils. To clean: wash with fresh water and scrub metal particles from the stones with a plastic scouring pad and abrasive powered cleanser.
Information from Spyderco