"Backup Power Source provides this battery backup system that keeps you in control of your power needs. This system provides clean, instant and reliable backup power to protect your home or business from power outages. Provides 4400 running Watts 8800 surge Watts of 120 or 240V pure sine wave power. Integrated inverter is prewired to internal AC/DC distribution center. Secures critical loads security system, refrigeration, sump pump, heating system, lights and more for up to 48 hours. U.S.A. Requires a licensed electrician for wiring and installation. Hardwired Yes, Modified Sine Wave Pure sine wave, Rechargeable Battery Bank Yes, Battery Type 105Ah AGM, Run Time hrs. 48, Allows Backfeeding of Power No, Alternative Power Collection Yes, requires charge controller and wind turbine and/or solar panels, Amps 35, Dimensions L x W x H in. 34 x 15.5 x 55, Power Volts 120/240, Surge Watts 8,800, Flex Standby Yes, Electrician Required Yes, Batteries qty. 8, Works With Gas Generator Yes, Automatic Switch Back Yes, Extended Run Yes, Running Watts 4,400, Solar Power Compatible Yes. Monitors utility power seamlessly and automatically transfers electricity to power management system When utility power is restored, automatically transfers back and recharges battery system Works with alternative energy sources solar, wind and hydroelectric and/or a generator Can be used for off-grid applications Modular design allows for expansion Includes eight 12V, 105Ah maintenance-free batteries Requires a licensed electrician for wiring and installation Includes lockable UL listed enclosure"