Type A Point / Sharp Point: This is the common thread-forming screw design used in most sheet metal screws for thin metal (.015” - .050” thick). Can be used with pre-drilled or punched holes in sheet metal, resin impregnated plywood, asbestos combinations, among others. 

Type AB Point: A thread forming screw combining locating point of Type A with thread size and pitch of Type B. 

Type B Point: This thread-forming screw is used in heavier metal (.050” - .200”). The larger root diameter with finer thread pitch is suitable for light and heavy sheet metal non - ferrous castings, plastics, impregnated plywoods and other materials.

Type 17 point: A thread cutting screw for wood with a coarse tapping screw thread and a special long sharp point fluted to capture chips.