Milwaukee 48-20-8344 MX4 4-Cutter SDS PLUS Carbide Rotary Hammer Drill Bit, 5/16” x 12”Milwaukee 48 20 8344 is an SDS PLUS MX4 4 cutter carbide rotary hammer drill bit intended for concrete and masonry, including concrete with rebar. The solid head carbide and 4 cutter geometry are designed to reduce rebar lock up, and the variable flute design helps clear dust faster to reduce heat buildup during drilling. Specifications Brand: Milwaukee MPN: 48 20 8344 Diameter: 5 16 Overall length: 12 Usable length: 10 Shank: SDS PLUS Cutter