Combines 12'' x 3'' double sided diamond stone with a strong magnetic base that holds the stone in place. Stone has a continuous diamond surface. Coarse 45 micron/325 mesh grit to quickly restore a neglected edge and Extra coarse 60 micron/220 mesh grit for use when significant removal of material is needed for damaged edges. Accommodates a variety of tools and blades. The magnetic base offers knuckle clearance for sharpening tools and knives. With the system it is easy to secure, change and remove the bench stone from the magnetic base for quick grit changes during sharpening.