... Wide Input voltage windows8.Pure sine wave output with less than 3% THD9.Expandable backup time10.Generator compatible11.Cold start12 ... indication LCDInput,oupt,battery voltage,frequency,load rate,UPS state, temperature LEDMain input , bypass,Inverter,Battery,Over load,Fault Efficiency ... .A Audible Noise<55db (at 1 meter) Environment Temperature0--40 °C Humidity0%-95% Low Frequency Online UPS TA2K-20K