Amptronix 12V 600W Pure Sinewave Inverter with Transfer Switch (ATS600-12A-ALT) Continuous Output Power 600W; Surge Power 1000W Output Voltage 115V+/-3% / 240V+/-3% Harmonic Distortion &lt;3%; Max Efficiency 85% No Load Current Draw 0.85A Low Battery Alarm 10.7V; Low battery Shut Down 10V