Be careful with these, there are fakes everywhere and they’re not always super obvious; I’d be even more concerned where the original box might not be available, because often the biggest tells are in packaging errors.
Fakes can have real serial numbers and everything, but they’ll sound like garbage, ‘Hey Siri’ won’t work, noise cancelling options might seem to be there but don’t really do anything, etc.
I think the biggest/most consistent indication you’ve got a fake is this:
The ‘Digital Crown’ should turn smoothly, without physical bumps. As you turn it, the headset gives a little haptic feedback, but the amount of resistance it takes to rotate the crown should never change. I saw a fake once that looked absolutely perfect, but the crown had physical detents alongs its rotation, so you’d start turning, it would take progressively increasing force to continue, then you’d get a ‘click’ as you passed the detent and that would repeat.
Hi there. Thanks for the class on fakes.
We buy from reliable vendors. 
I believe you, and didn’t mean to imply otherwise! I’ve never been anything but happy with Woot, but I thought sometimes stuff sold here came from Amazon inventory? That’s where the pair of fake AirPods Max that led me to learn they existed in the first place came from, so I figured it might be worth giving folks a heads up. No disrespect intended!