The Hitachi 728699 Nickel Plated Impact Rated Torsion Bit Set with DuraCore has been made with an advanced hardening process and nickel plating which results in a stronger, more durable bit that provides higher torque and increased driving power. Hitachi DuraCore treated products are manufactured utilizing a proprietary treatment superior to cryogenic treatment. This treatment strengthens the molecular structure of the metal through to the core. DuraCore is not a coating, so it will never wear off or chip away. Hitachi DuraCore products are revolutionary and no other untreated accessory of similar metal will compare in cutting speed, wear life and durability. This kit includes (3) no.1 Phillips bits, (9) no.2 Phillips bits, (3) no.3 Phillips bits, (2) no.1 Square bits, (7) no.2 Square, (3) no.3 Square bits, (1) T15 Torx bits, (1) T20 Torx bits, (2) T25 Torx bits, a 1/4-inch magnetic insert bit holder, a Hex shank with ball dent (23/8-inch length), (1) 1/4-inch, (1) 5/16-inch and (1) 3/8-inch Hex shank nut driver with ball dent and (1) tough latch case (Dark grey). The Hitachi 728699 Nickel Plated Impact Rated Torsion Bit Set with DuraCore is warranted to the original purchaser to be free from defects in materials and workmanship for a period of 30-days from the original purchase date. Every Hitachi accessory is designed to the highest standards and is rigorously tested for both performance and durability. Since its inception, Hitachi has pioneered innovative technologies that have improved the quality of craftsmanship worldwide. Hitachi is a leader in power tool research and development and has achieved many firsts in the power tool industry. Today, Hitachi continues the tradition of innovation and engineering with new features in addition to classic quality.