Models DGA900 are high powered 230mm (9") cordless angle grinders powered by two 18V Li-ion batteries in series. The 36v DC motor delivers more power and run time without leaving the 18v Lithium-ion platform. Featuring Automatic Torque Drive Technology (ADT): Automatically changes the cutting speed according to load condition for an optimum operation. Active Feedback Sensing Technology (AFT): Shuts down the tool to protect the user if the rotation speed suddenly slows down. Battery & Charger are sold separately.