3pcs HSS Steel Step Cone Drill Hole Cutter Titanium Bit Set 4-12/20/32mm. Our step drill bits are then coated with titanium for superior durability. 4 ~ 32mm (4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32mm), 6.35 mm shank.
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