This 600 watt pure sine inverter charger, ETL Listed to conform with UL 458 standards, is a combination of an inverter, battery charger and AC auto-transfer switch into one complete system with a peak DC and AC conversion efficiency of 80%. It is packed with unique features and it is one of the most advanced inverter chargers in the market today. It features power factor corrected, sophisticated multi-stage charging and pure sine wave output with unprecedentedly high surge capability to meet demanding power needs of inductive loads without endangering the equipment. The AC/Battery priority and auto generator start functionality make it suitable to work in either backup power or renewable energy applications. When customized to Battery priority mode via a DIP switch, the inverter will extract maximum power from external sources and renewable energy systems, with only minimal battery cycles being required. The overloads capacity is 300% of continuous output for up to 20 seconds to reliably support tools and equipment longer. In AC priority mode, when utility AC power cuts off, the transfer relay is de-energized and the load is automatically transferred to the inverter output. Once the qualified AC utility is restored, the relay is energized and the load is automatically transferred to AC utility. When switching to battery priority mode via the DIP switch, the inverter will extract power from external power sources in renewable energy systems and a minimal cycle of the battery will be required. With the availability of the auto generator start, an electrical generator can be integrated into the system as a backup and started when the battery voltage goes low.