The DongCheng 20V MAX Brushless Cordless Rotary Hammer is a high-performance power tool that uses a brushless motor to deliver 2.1 Joules of impact energy for fast drilling in concrete. The lightweight and compact design makes this cordless rotary hammer ideal for concrete forming, railing mounting, structural connections, and other working conditions. This cordless rotary hammer has a maximum drilling diameter of 7/8'' and additional performance features such as variable speed functions, a built-in LED light, and efficient heat dissipation.