Widely used: Our multifunctional drill bits with sharpened cutting edges for multi-purpose drilling on drywall, brick, tile, wood, aluminum and sheet metal. Spearhead design Strong tungsten carbide tip can easily penetrate various materials and reduce chipping. Efficient Design: The drill with triangle shank handle prevents slipping and allows the drill to be held and stabilized in the power drill. The U-type slot design enables perfect chip removal in the whole sandblasting treatment. No broken edges, no shaking, low cutting resistance, fast hole speed, easy chip removal. Material: High quality tungsten carbide ultimate punch bit, which can prevent cracking and provide longer service life, strong and durable. 2 flute design for better removal of drilling dust. Dimension: multifunctional drill with 7 different sizes, 3mm/4mm/ 6mm (1/4"), 8mm (5/16"), 10mm ( 3/8", 12mm(1/2"). Warm Tips: The multi-functional drill bit is resistant to high temperature around 1000. Long time work can exceed 1000 the head, however, burn out. It is therefore necessary to add water when drilling on material with high hardness. These drill bits can be used for loading drill, hand drill, bench drill, etc. Do not use the impact mode of drills or hammers.