I'm using an older RemStar M series. It connects directly to any 12Vdc
female receptacle, no need for an inverter at all.
Depending on your circumstances & if your insurance is buying you a new one, if not, I purchased a low hour used one on Craig's List & reset the pressure myself. It is dedicated for TT use, as I have another one in the S&B. It's my understanding that most Respironics units will function this way with the right adapter cord.
I also use a dedicated 35amp AGM battery for mine. Very small & compact.I don't use the humidifier & mine will last for 3-4 nights before recharging the battery. I would assume with a humidifier, maybe 2 nights.
Here is a pic of my adapter cord. It plugs directly into the CPAP
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