BJJ belts for the big and tall

Hey guys, we've got what I hope isn't a totally unique situation that I'm hoping someone in the community could lend some direction. At our club, we have a couple of folks that are getting close to the point of getting their blue belt. We're trying to locate a belt that can be traditionally worn by one of our students who is difficult to fit. He's 6'5'' and 400lbs+. Does anyone have any experience with finding a rank belt for someone approaching his size? The biggest we've run across thus far has been A5. Any ideas?



Thanks in advance for any advice.