1. Reversible. Automatic cartridge design. 2. Stepless. 3. 21+1 stall torque adjustment. 4. Waterproof, drop, leakage power. 5. ECP: battery protection device to prevent battery overload, overheating and deep discharge. 6. Integrated LED light for illuminating the work area can also be night work. 7. Twisted soft grip handle CST operator to provide excellent grip and a sense of comfort. 8. The fast slow adjustment.