Shockwave Impact Duty 3-piece step bits are engineered to deliver the most durable and fastest impact step bit hole drilling solution. These step drill bits give best-in-class performance in impact drivers with the versatility to be used in drills. The 1/4 In. hex shank has an optimized SHOCKZONE body providing you with the industry's most durable shank, reducing early shank breaks. A TiAIN (Titanium Aluminum Nitride) coating helps deliver 5X longer life, while the step drill bit's Rapid Strike tip and dual spiral flute produce 2X faster holes. Step drill bit kit features the #1 1/8-1/2 In., #2 3/16-1/2 In., and #4 3/16-7/8 In. step bits with laser engraving for a clear stop on size identification.