Tim, I am no expert on the American pump but I can tell you the 12.5" x 25.5" cylinder does exist for the American pump. The octagon 2487 is one of my favourite visibles and I had purchased 2 cylinders in advance (12x27") of buying my octagon. I purchased cylinders by using chart sizing information that was wrong. I was fortunate enough to measure an original damaged cylinder that was still on a 2487 octagon and it measured 12.5" x 25.5". I wish I had of known this earlier. You are doing the right thing in correcting wrong info that exists out there. Good stuff.
Last edited by Gasoline George; Tue Mar 22 2016 01:27 AM.