I bought this in Korea. It doesn't seem to be a Japanese standard, as I couldn't find the same product in Japan. It's labeled as 2XL, but it fits quite tight on me (180cm, 75kg), so I think the sizing runs small. Therefore, I'm listing it as a size L equivalent. Only tried on indoors. I haven't been able to authenticate it. Returns are not accepted after purchase, so please make your decision carefully before buying.