Material: HSS. These central drills provide fast cutting speed and good chip removal. Size: 1.0mm, 1.5mm, 2mm, 2.5mm, 3mm, 5mm. Feature: Each drill bit has a double end and is ground with a standard angle of 60 degrees inclusive. Suitable for: Bodhi jewelry, ordinary steel, metal, iron, copper, aluminum, wood, plastic, etc. p> Function: used for prefabricated precise positioning in hole processing and guides the twist drill for hole machining to reduce errors. Color: silver Material: high speed steel Weight: 60g Product use: prefabricated precise positioning for hole processing, twist drill guidance for hole processing, error reduction, center drill is used for processing center holes on the face of end of shafts and other parts. Quantity delivered: 6pcs/set