3pcs Set 4-12/20/32mm Large HSS Steel Step Cone Drill Bit Hole Cutter. 4-32mm: 4,6,8,10,12,14,16,18,20,22,24,26,28,30,32mm. Material: HSS steel. 4-32mm: 10mm (Approx.). 3pcs Set Step Drill Bits. 4-20mm: 4,6,8,10,12,14,16,18, 20mm.
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