Constructed from alloy steel with fully heat-treated for durability and hardness above carbon steel, the with the polished is made to and high wear resistance. The with double-side cutting spurs of high quality grabbing wood and carving it away, creating beautiful holes with reduced breakout. Accurate drilling on wood, fiberglass, plastic, PVC (Polyvinyl Chloride). Includes 13 high-quality spade drill bits, Size 1/4Inch, 5/16Inch, 3/8Inch, 1/2Inch, 9/16Inch, 5/8Inch, 3/4Inch, 7/8Inch, 1Inch, 1-1/8Inch, 1-1/4Inch, 1-3/8Inch, 1-1/2Inch. The hex shank is 1/4 with groove for reducing slipping and preventing falling off, universal for the most drill driver tool of in the markets. Colour:As Shown Material:Metal Package Contents: 1set * Spade Drill Bit Sets Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.