Left Hand Design: 29 sets of left hand drill bits include 1/16″, 5/64″, 3/32″, 7/64″, 1/8″, 9/64″, 5/32″, 11/64″, 3/16″, 13/64″, 7/32″, 15/64″, 1/4″, 17/64″, 9/32″, 19/64″, 5/16″, 21/64″, 11/32″, 23/64″, 3/8″, 25/64″, 13/32″, 27/64″, 7/16, 29/64, 15/32″, 31/64″, 1/2. The left-hand design can also be used in conjunction with a screw extractor, can meet more needs M35 Cobalt Drill Bit: The M35 cobalt drill bit is a durable, sharp and robust drill bit suitable for cutting stainless steel, iron castings, copper, aluminum and other soft metals as well as plastics, wood etc Quick and Efficient: The cobalt drill bit set can be used effectively on most soft and hard objects, with a 135 degree point tip and twist design for faster cutting, self-centering to prevent walk-off and faster chip and particle removal HSS Drill Bit Set: HSS cobalt drill bit set for hardened steel with excellent cutting performance. 13 sets of drill bits for long term use. The inserts are hardened and polished for improved sharpness and precise cutting without wobbling Easy Storage: The drill set includes a drill case with size indexes and is packaged in a small package for easy storage and sorting. If you have any questions, please refer to us and we will be happy to help you.