Note: I use my own terminology in this video and this likely isn't technically what 'phase correction' means in inverter spec sheets. However inverter products which advertize this feature seem to also have the 'better' method of making modified sine outputs. As far as I know this is something you will need to verify yourself - something you can do by comparing the readings of an RMS DMM to that of a non RMS DMM under both high and low battery voltage.