I agree with Miss Prissy. The AA machined from one solid piece of metal, the tops are machined for a perfect fit. They run about $250, at least they did a few years ago. If I had it to do all over agian, I'd buy one at a garage sale or second hand shop, Craig'sList (Mirror, Presto whatever, quality wise they are all about the same.) Then save up enough to buy a All American. You could drive over it with a tank and the worst that would you may break a clamp, which are easy to replace. Your grandkids will still be passing this thing on. They are that good. Also, because they are machined not stamped they are more efficient to use. My AA reaches pressure probably 10 minutes before my other one does.
Bob