Lost the third 20 # tank of CO2 in the last three months today from crappy air manifolds. They are from morebeer, the type that add on one more line at a time. The brass itself is prone to cracking right at the threads for the valve. One I probably overtightened the valve when changing a line. But the other two went on their own. I don't run them at high pressures either. They were perhaps two years old tops. Cheap. Gas is really expensive out here. All kines.