... charger *wide input, accurate output *AVR function *low frequency transformer *rack or tower design 300w dc to ac inverter Main features ... power inverter 2.12/ 24VDC optional3.Pure sine wave4.Low frequency, inbuilt transformer.5.AVR function6.Charge current ... test, discharge protection, over charging protection, short-circuit protection.low voltage, over voltage,over load,over heating protection etc. ...