looking for a dc to ac converter that will give me 550 watts at 4.5 amps. will be used in my tow vehicle and van to power my oxygen generator. Any help appreciated.
The oxygen machine may have a start up surge. Try to find out what that is. It may be triple the run wattage.
Buy an inverter which will cover the start up surge.
It will need to be a pure sine wave inverter. Here is one that is 2000 watts and inexpensive. http://www.bestconverter.com/Prowatt-SW2000-Sine-Wave-Inverter_p_375.html#.WOXP0ri1u1s