Milwaukee SDS-MAX MX4 1-5/8" X 18" X 23" features the MILWAUKEE® MX4™ 4-Cutter SDS Max Rotary Hammer Drill Bits designed with solid head carbide for up to 5 times longer life when drilling concrete with rebar. These bits are engineered with rebar guards to ensure maximum durability in tough aggregate and rebar conditions. Milwaukee’s MX4™ 4-Cutter bits include sharp centering tips for precise spot drilling in concrete, while the integrated 4-cutter design prevents lock-up in rebar, minimizing downtime during use. Optimized flutes efficiently remove dust, reducing heat buildup and allowing for up to 15% more holes per battery charge. Each drill bit also features a wear mark indicator that signals when the bit no longer meets ANSI requirements. These drill bits are i for use in concrete with rebar and masonry applications, making them a reliable choice for professionals seeking durability and performance. Model Number: 48-20-3991