Pure Sine Wave Output : Smooth and perfect pure sine wave output, just the same as home power/city power, Provide max 4000 watt continuous power and 8000 watt peak power at 60Hz frequency, power your 110v 120v ac appliance with a 48v power battery bank (battery voltage 40v to 59v is acceptable) Fully Safety Protections : The pure sine wave inverter has high efficiency and stable performance. It has sound protections including overload protection,over current protection, short circuit protection, battery reverse connection protection, high temperature protection, high or low battery input protection, built-in fuse protection. Grounding of the built-in wires of the inverter : Grounding wires have been installed inside the inverter, no external grounding wires are needed, which is more convenient and safer to use. The pure sine wave type can avoid wasting energy during transmission. Extended Inverter Life : Input/output isolation design and soft-start technology, large durable aluminum enclosure provides advanced drop and shock protection. Intelligent quiet cooling fans ,less than 50 DB when running , help reduce heat and prevent short circuits. Ideal mobile power : Electronic devices are integral part of our lives. When traveling in car, RV or boat,semi-trucks, during camping or other outdoor events,we need the mobile power solution for electronic equipment. The pure sine wave inverter is an ideal power back up for emergency or home power outage. What you get : A 4000 watt pure sine wave inverter, a instruction manual, 2ft Battery Cables (black and red), a friendly and patient customer after-service, Spare fuses ,12-Months Warranty. Details DC input: 48V DC input range: 42V-58V No Load Current Draw: 1.1A Efficiency:90% AC output: 110V~120V AC Regulation:3% Frequency: 60Hz Socket:15A USA type Low Voltage Alarm:41V-43V Low Voltage Shut Down: 39V-41V Over Load: shut off, recover manually Over Voltage Shut Down:60V Over Thermal: Shut Off Output Automatically Over voltage protection: Cooling Fan will run when the temperature is over 45 Centi degree / 122 Fahrenheit degree