Replacement 6 1/2” diameter masonry blade for Crain No. 800 Super Saw, No. 810 Super Saw, No. 812 Super Saw, No. 820 Heavy-Duty Undercut Saw, or No. 825 Heavy Duty Undercut Saw. This is a dry abrasive cutting composition blade for use in undercutting masonry walls or hearths. Produces approximately seven to ten feet of undercutting depending on material and depth of cut. For use in undercutting masonry materials only. Not for use in cutting any kind of metal. Starting diameter: 6 1/2“, thickness: approx. 1/8“. Net weight: 6 oz.