High-speed steel spiral groove nitrogen step drill 4-32mm step drill multi-purpose drill 3-piece set

The specs of the three-piece set of nitride black step drill are:

4-12 :4 6 8 10 12 (5th order)-weighing about 16G
4-20 :4 6 8 10 12 14 16 18 20 (9th order) -- Weight about 47G

4-32 :

4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 (15th step) -- weighs about 155G

4-32 single unpackaged, slightly different from the appearance of the suit 4-32 there is no cross-cutting groove in the head (see the selection diagram for details) three-piece set for plastic bag packaging