Designed to drill in multiple materials including brick, limestone, slate, block, tile, metal, cast iron, wood, drywall, gypsum board, plastic, and marble. High speed steel with 4 facet diamond ground carbide tip. For use with corded or cordless drills. Set includes 1 each: 1/8'' x 3'', 5/32'' x 3 1/2'', 3/16'' x 3 3/4'', 1/4'' x 4'', and 5/16'' x 4 3/4''.