The Milwaukee 48-89-2331 Cobalt Red Helix Twist Drill Bit Set is a 15-piece set designed for drill drivers. The bits are made of cobalt material and steel, ensuring durability and long-lasting performance. With a 3-flat shank style, these twist drill bits from Milwaukee are perfect for various drilling tasks in the workshop or home. The set includes different sizes and types of twist drill bits, making it a versatile and essential addition to any toolbox.