Historically, the alpha numeric sequence of wash codes has no bearing whatsoever on the jeans. Those codes are random so I wouldn't pay any attention to that. I have this wash in shioner it's quite nice. Denim is mid gauge. At a guess I'd say 10.5oz with a little elastine that adds more "give" to the jeans rather than making them stretchy. All in dark raw colour. I would size down though. This wash runs big.