Stanley 500 Watt Power Inverter with Dual 3.1 Amp USBGet 500 Watts of continuous AC power at the worksite, campsite, or in your car with the heavy duty Stanley PI500S 500 watt power inverter Provides on the go power with a lightweight, ergonomic design that charges up to 4 devices at the same time Connect the clamps to your vehicle battery for 500 watt continuous power; Use the 12V DC adapter inside your car for 120 watt power Dual 120V AC electrical outlets and dual 3. 1 Amp USB ports allow you to