Milwaukee's 3-flat Secure-Grip™ hammer-drill bits provide superiority in regards to quality, performance and longevity of life. The 3-flat Secure-Grip™ shank is designed to fit in all 1/2 In. three jaw hammer-drill chucks and reduces the possibility of the bit spinning in the chuck during heavy torsional loads. The bits drill faster and last longer than other hammer-drill bits on the market due to their reinforced flute geometry and carbide tip design. Milwaukee's offering has a range of diameters from 1/8 In. to 1 In. with lengths up to 18 In. Seven piece kit.