Bi-metal hole saw. Constructed from M42 high speed steel with 8% premium cobalt content, resulting in high-strength, greater wear resistance and less prone to chipping. Rigid solid steel back plate for clean true holes and longer tool life. Unique fleem ground teeth design results in improved performance and efficient chip removal. 4/6 variable pitch geometry cuts down on harmonic noise to minimize tooth strippage. Featuring a 1-7/8 inch depth of cut, reducing cutting time with a single pass design. Diamond sides provide quick plug removal, available on 7/8 inch to 6 inch hole saws. Cats eye openings on solid back plate provide line of sight and aid in plug removal, available in 2 inch to 6 inch hole saws.