Bosch HD18-2 Two-Speed Hammer Drill, 1/2" Powerful 8.5 amp motor for high-torque and high-speed drilling capabilities Auxiliary handle with built-in depth gauge securely locks into place and provides consistent drilling depth Integral slip clutch - more user security because it disengages the output shaft should the bit get into a bind situation Securely clamping 1/2-Inch three-jaw chuck for rugged hammer-drilling applications Dual-mode selector easily converts from rotation-only to hammer-drill mode