Use one bit to drill multi-sizes of holes. And it will run cooler and stay sharper thanks to a titanium nitrite coating. Compatible with all corded and cordless drills with chuck size of 1/4" or larger.

Idea for drilling up to 5mm thickness carbon, iron, aluminium, brass steel, and PVC materials, not for stainless steel .

1/4" hex shank suits quick change adaptors ensures a solid connection with the drill chuck.

To extend the working life of the bits, using cooling water or liquid when drilling, recommend 

Individual or 3pc set:

1. 4-12mm 4,6,8,10,12mm 5 steps bit
2. 4-20mm 4,6,8,10,12,14,16,18,20mm 9 steps bit
3. 4-32mm 4,6,8,10,12,14,16,18,20,22,24,26,28,30,32mm 15 steps bit
4. 3pc set included: 4-12,4-20,4-32mm 3pc step drill