Carbon steel hole saw: 1) High carbon steel, hardened teeth, safety and longer life 2) Regular teeth: 4/6 TPI 3) Diameter from 3/4" -51/2" (19-140mm) 4) Cutting depth: 25mm 5) Used for cutting wood, wood, wall board, plastic and soft metals 6) Extra charge for pilot and arbor Tungsten carbide gritted hole saw: 1) 2-1/2" cutting depth 2) For the builder, tile setter, home owner, do-it-yourselfer, construction worker and other professionals 3) Designed to be used with any variable speed hand drill 4) Diameters from 1-1/4" - 4" (33 - 103mm) 5) In blow case