The SDS-Plus MX4 drill bits from Milwaukee are engineered for the toughest concrete and rebar applications. Featuring fully welded solid carbide tips (up to 20 mm), they offer maximum durability and fast drilling speed. The 4-cutter tip combines a sharp centering point, rebar guards, and dust grooves for clean starts, precise holes, and long life even under extreme jobsite conditions. An optimized flute design with a reinforced core and alternating SPEED and HEAVY-DUTY spirals ensures fast debris removal, reduced friction, and superior stability. The convex shank maximizes energy transfer from tool to tip, boosting impact force and drilling efficiency, while one-piece slotted carbide tips for diameters over 20 mm provide exceptional strength and break resistance. PGM certified and made in Germany, these bits deliver precision, reliability, and uncompromising performance on every jobsite.