Core Center Bit: 5 in Core Dia, 5 Decimal Equivalent, 7 in Max Drilling Dp, 12 in Overall Lg

BOSCH MODEL HC8070, These one-piece core bits have a spline shank that prevents the bits from slipping in high-torque drilling applications when creating large, shallow holes in concrete, masonry, and limestone. The bits install into compatible rotary hammer drills with spline-drive chucks, which have 12 grooves that mesh with grooves on the bits' shanks to hold them in place in the chucks. The bits are secured with a retaining pin.