It's a portable unit made by a company called Zena, Inc. It's a welder packed into a large GM alternator case. It's probably one of the best purchases I ever made. You can run it from any gas motor. Mine is piggy backed to the alternator on my old farm truck. You can use a small gas motor, a riding lawn mower, a tractor, etc. The positive electrode clamp contains all the welder controls so you have control of the welder at your finger tips at all times.
It's high frequency DC, so you can also TIG weld with it. And you can weld in either + or - polarity.
I just park my truck outside the shop door when I need it. I have used it all over my place, for everything from coral fencing to, well, smoker building. I also have a Lincoln MIG welder and a Lincoln arc welder and I use the Zena most of the time.
If you are interested you can find them at
www.zena.net . You can buy one from them through eBay for a little less than they sell them on their website.
This would be a great welder for someone that doesn't have a lot of room or even a shop, because you can adapt it to any car and it's always under cover because it's under the hood. It's very easy to operate and would be good for someone that has a lot, little or no welding experience, because it's such a forgiving machine. And 150 amps, 100% duty cycle for 500 bucks is unbeatable. It will go through 1/2 inch plate like a hot knife through butter. I know because I have done it.
If you would like, I can post a pic of my truck underhood.