The BLG-Series is a brushless electric screwdriver designed for high production environments at an affordable price. Minimal heat build-up even when tool is operated continuously. Provides precision torque control with an automatic shut-off clutch once preset torque is achieved. Features a high performance brushless motor design that provides durability and reduces the standard maintenance costs of electric screwdrivers. With almost no expendable parts and simple design, the brushless screwdriver life cycle is extended and maintains a clean working environment. Requires transformer (power supply). Model:BLG-4000X Drive Size:1/4" F/Hex Range: 10 - 55 cN.m ,0.9 - 4.8 lbf.in, 1.5 - 5 kgf.cm. Tool Weight:13.1 oz. Tool Length:8 RPM High:1000 RPM Low:690 Grip Dia:1 1/4" Bit Hex Size:11/32" Square Drive Size:1/4" Bit Length (in):1"