1x 0.5mm Drill Collet. 1x 1.0mm Drill Collet. 1x 1.5mm Drill Collet. 1x 2.5mm Drill Collet. 1x 3.0mm Drill Collet. It is suitable for 0.5-3.0MM drill bit. For small drills, after connecting with the motor, drill holes for the PCB circuit board with special micro drills.
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