Carbide-tipped replacement blade for the Crain No. 812 Super Saw, No. 820 Heavy Duty Undercut Saw, or No. 825 Heavy Duty Undercut Saw. The large Six and a half inch diameter allows these Crain saws to fully undercut inside corner areas. The 40 carbide teeth and precision formed steel blade body produces smooth and accurate cuts. For use in undercutting wood doors, wood jambs, wood base or drywall only. Not for use on any metal, masonry, stone, or ceramic tile materials.