Cobra CPI M400 Marine Power Inverter (400 Wt Continuous, 800 Wt Surge) Cigarette lighter cord Ground Fault Circuit Interrupter AC outlets - Shock Protection for safer operation in marine environments Conformal Coating on all electronics - Corrossion Protection Pentagon Power Protection - Thermal Shutdown, Reverse Polarity, Over Voltage Shutdown, Low Voltage Shutdown, Low Voltage Alarm To determine required wattage for a device: 1 - Look up required Amps a device is rated (on ID tag on back of unit) and 2 - Multiply Amps  Volts = Watts Power small appliances (mixer/blender), audio and video equipment (video game systems, 19" color TV), mobile office equipment (laptop computer, fax machine), battery chargers, power tools (finishing sander, drill)