JAM,
That IS a single stage compressor, with aluminum head. You have been warned, err...advised.
It's ok for limited use, bycycle tires, blowing out plumbing lines, etc. 6 HP may seem lilke a lot of horses for a compressor, but it will run non stop. Admittedly, most of us are thinking DA's, airboards, grinders, and impact guns, but you will have to trust me on this one, when you buy the compressor all these new toys will follow--and you will use them!
DV