These revolutionary abrasive films, developed by 3M, are manufactured to an extraordinary level of precision and durability. The abrasive is bonded with resin to a very tough, waterproof mylar film. 3M MicroFinishing film cuts quickly and produces an excellent finish. They can be used for sharpening everything from plane blades to razors but are at their best with carving tools. The film can be easily cut and applied to a backing of almost any shape. The 12 micron (#1200 grit) quickly removes steel, while the 5 micron (#2500 grit) refines and produces a keen edge. The 0.3 micron (#18000 grit) leaves a mirror finish. For the best edge, use the 1 micron (#8000) prior to the 0.3 micron. One sheet can make a number of specialized hones and strops.