The exclusive TwinLand dual land design of these drill bits improves accuracy and eliminates burning. The second land provides improved guidance when hand drilling and seals the flutes to prevent chip squeezing and burning. The unique brad point tip design produces cleaner holes while providing pin point accuracy. Durable bits have roll-forged flutes and diamond ground tips for sharper, longer life. Fits all 3/8-Inch and larger drill chucks. Made in Germany. Imperial set includes 1/8, 3/16, 1/4, 5/16, 3/8, 7/16, and 1/2-Inch diameter bits.