EZELAP Diamond Products Special Use Files Model 11 6" x 1/4" x 1/4" Code Description 11F 6" x 1/4" x 1/4" Metal Substrate Diamond grit: Fine (600) 11M 6" x 1/4" x 1/4" Metal Substrate Diamond grit: Medium (400) 11C 6" x 1/4" x 1/4" Metal Substrate Diamond grit: Coarse (250) 11SET 6" x 1/4" x 1/4" Diamond File, Fine, Medium and Coarse.