The Lucas 2! Our company carries these as well, they’re preferred over manual compressions and run at a steady 100 per min. We use these as often as we can so that we can focus on anything else that may be necessary and not worry about if the patient is getting the correct CPR. We always make sure our batteries are charged. Before you say anything though, we keep up on all of our certifications and do not put our own ability aside that of a machine, we use it as another hand and it has come in use!
Every service in my state has one of these bad boys.