never heard that name before, but it looks like just a PET carboy similar to a Better Bottle or any other brand. For what its worth, my PET carboys match up roughly with identical volume glass carboys.
I just bought two 6 gallon bubblers from Northern Brewer.
Each one measures 21" tall and 11 3/8" in diameter and I think that makes the circumference 35.74...roughly. You'll have to factor the airlock of course. I use these bungs which results in the airlock sitting lower than when I used the other kind of bung: