So I have a few humvees to move coming up soon and I decided that since a few of them cut off when the slave cable is removed, I'd find a more portable setup. Checked all around and the Jump N Carry JNC 12/24 had pretty good reviews, so I coughed up the $325 for it. I figured it would be as simple as making a second cable with a NATO plug to hook up at the back of the box. Not quite that simple. After examining the wiring diagram, there's a lot going on inside that box and all that 24v plugin does is loop the two 12V batteries to series. The juice only comes out of the leads, so I cut off the alligator clamps and put quick disconnects on the box, the slave and the clamps. I tested on one of my humvees with caved in batteries and zero volts and it had enough a** to crank over quick and start. Very happy with it so far.