The DC 12 V jack is compatible Respironics products that accomodate DC cables. The cables will charge your machine when you aren't connected to a wall outlet, which is great for frequent travelers and people who are frequently on the road.
Connect to 12 V Battery Sources
The cable will connect to any Respironics machine compatible with 12 V battery sources. One end attaches to the machines voltage jack, and the other side plugs into an energy socket.
The DC 12-Volt power cord is compatible with all Respironics M Series machines, all PR System One machines except 60 series models, REMstar machines, Synchrony machines, Sandman Series machines, IntelliPAP Series machines, and the GoodKnight machines.