50 hz line interactive sine wave mosfet based ups have a wide input variation range covering 160 to 280 volts as as well as facilities for low and high voltage cut off sine wave output [50 hz] free from spikes rf noise and em noise in the presence or absence of utility power these systems are also insulated against over charging discharging cut off and overload the other features include audio visual indications for mains normal/mains failure/battery low/overload etc the models are available in 500 va/625 va and 1000 va versions