These PSU's are handy. My neighbor had been traveling, and her son's car was parked in her garage for a few months. So she gets back and goes to start it today, and of course the battery was very dead. And since the car was pulled into the garage, neither of us had long enough jumper cable to reach the cars battery from a second vehicle. And I had lent my jumper box out to a friend. So enter Shirley PSU. Set it to 14.4V and 31A.(the highest it will go powered by a US 110VAC standard outlet) and connected it to the dead battery. Current flow was initially very low, but it eventually climbed to 31A. Then we let it charge the battery for another hour or so. After which it started right up!
