The Irwin Tools - Hanson PTS (Performance Threading System) Taps and Dies are the most innovative products in the threading industry in decades. With an increased flute taper in the taps, the new products are 20% more durable and up to 30% easier to break chips with. Irwin has also added self aligning taps to the program by creating an alignment chamfer (tap tip) that easily allows the user to start threading straight with ease. The new rolled thread dies with Irwins patent pending self aligning guide system provided less chance for cross threading, greater thread quality, greater accuracy and greater cutting ease. On top of the new Taps and Dies, Irwin has also redesigned the entire drive tool system. With a die lock ergonomic die handle that also accepts two different adjustable tap sockets, this all encompassing drive tool set will make the job easier for every threading application. KIT : 17 Standard Taps 17 Standard Dies 17 Metric Taps 17 Metric Dies 7 Piece Drive Tool Kit Threading Tools : TAP DRIVER – SMALL: ADJ TAP SOCKET DRIVES TAPS SIZES NO. 4 (3MM) TO 1/4" (6MM) TAP DRIVER – MEDIUM: ADJ TAP SOCKET DRIVES TAPS SIZES 1/4" (3MM) TO 1/2" (12MM) DIE STOCK: DRIVES 1” HEX DIES WITH AND WITHOUT ALIGNMENT, ACCEPTS SM & MEDIUM ADJ TAP SOCKETS Metric Pitch Gauge SAE Pitch Gauge DIE SPACER BULK, HEX - IRWIN T-BAR FOR ADJ. TAP SOCKET BULK. This set also comes with all of the drill bits recommended for each tap i nthe set, making this a one stop shop for your threading needs.