Originally Posted by Monster Mash
A corny is only 5 gallons, that keg is 2 cornies welded together to make it 7 gallons, that is why it is $150.
They say they added 7 inches to the height for a capacity of 6.6 gallons. I don't have a corny to measure the stainless steel part of it, but I'm betting they could get three 7 inch sections out of a corny, or maybe a couple of 7 inch sections out of a damaged one. Nice way to use up otherwise useless scrap cornies.
It seems like a perfect fermenter for 5 gallon batches at that price point. Extremely strong and durable, and several will fit in a full-size fridge for lagering. The price certainly seems right, considering that you can ferment a full five gallon batch in one, then use CO2 pressure to rack to a secondary regular 5 gallon corny for conditioning then serving. You'd be able to collect the yeast and trub slurry, wash it, and save the yeast in the same you would with a glass carboy after racking to secondary. I don't see any real disadvantage to using these in place of regular carboys, aside from cost, and there are undisputed advantages due to their durability and space-saving design.
If you just bought the lid that Yuri pointed out for $29 and used it with a regular-sized corny, how many gallons could you ferment in it? I know you need some headspace. Maybe 4 gallons?