Item Specifics: Material: High Speed Steel Length: Approx.130mm/5.12" Use: Metal Drilling DIY Supplies: Metalworking Model Number: 13cm / 5 inch Type: Center Drill Bit The use of the body spring generate punching power to shock. The end of the ball grip, more effort when in use. Gives precise starting point on steel and other solid materials Allows you to easily mark work using one hand prior to drilling which will pre vent the drill from slipping. Automatic spring loads then releases at top of cycle with force to create center punch (No Hammer Needed) Spring pressure can be adjusted by simply rotating the knurled top of the punch. Material: HSS high speed steel cutting edge,Hardness up to HRC58 ~ 60 . Handle Knurled steel body, Alloy steel point. Handle Diameter: Approx 1.3cm round shank Full length: 130mm / 5 inch. Features: 1,Suitable for punching sample holes before drilling on steel plate, aluminum, copper, wood plank and other materials to positioning holes, to avoid the direct drilling position will slip or occurs deviation which result in damaging the drill. 2,Using the tapered tip to drill small dot on workpiece, the small dot plays the role of center point or the mark of other point line position. Included: 1 X Center Punch