>>7215993just measured, 10 inches exactly. I'm not -that- tall, 5'8"--but that pic was taken about a month ago, so maybe they were a bit smaller then? I do have a small frame though, my wrists are 5.5" inches so I DUNNO MAN
To be fair your arms are pretty lean as well, I doubt they're as big as you seem to think!
Plus I'm mirin because you can do 5 pullups and I can't even do one :(