I finally found a battery that allows me to use heated humidifier and heated tube. My ResMed machine has automatic climate control. I can't sleep without running it. Yet, we have power outages frequently where I live and I don't dare to sleep without my cpap. Now I finally have a peace of mind that I can sleep through power outages. In fact, we just had one last week and I slept right through. I recommend it. It works as advertised.