Sorry but that is a fake. The most obvious part that shows it to be fake is the hook closure part for the top flap. Its supposed to be all metal. There isn't supposed to be any piece of black nylon material on it. I'm surprised that people keep falling for these fake Kitchen Sink backpacks. This part is the most easiest way to tell if its fake. Also, the red tab on yours is way too long and the overall look of the pack looks really off. Here is how the real and current red tab one looks...
Seriously guys, beware of fakes. Don't get ripped off unless you know you are getting a fake. Some of them are pretty easy to spot like what I mentioned above. The Kitchen Sink is a quality and rugged pack that can last years. I doubt a fake one will last as long as the genuine one after prolonged use.
Now this one here is the real one. This is the older variation of the Kitchen Sink with the metal waist buckles and metal side zippers whereas mine posted in my previous post is their latest and current version of the Kitchen Sink which has red tabs for the side zippers and plastic waist buckles.
I've yet to see a perfectly executed fake Kitchen Sink. There is always some sort of detail which shows it to be a fake. If not for the the hook closure, it can be the O logo, and on some fake ones, the zippers can be wrong. But its always the hook closure part that they get wrong on these fakes.