Self-sharpening, continuous rim carbide grit hole saw designed to be used with any variable speed hand drill 2-1/4 cutting depth Allows for easy removal of cut material plug Used in applications such as ceramic tile, concrete block, cement backerboard, brick, fiberglass, plexiglass, PVC, wood with nails, cultured marble, and dry wall Artu hole saws require Artu"s mandrel and pilot bit Dia. In=2-1/8