The new iPhone 6s went on sale over the weekend and broke previous models’ sales records, with Apple announcing that it had shifted more than 13 million iPhone 6s and iPhone 6s Plus units in just three days.

But what none of those buyers queuing up could have known (not even this robot) is that this year’s iPhone upgrades may well conceal an unadvertised, unofficial secret weapon: water-resistance.

Foolhardy YouTube user Zach Straley did a very brave thing – or a very stupid thing, depending on which way you look at it – with his freshly acquired iPhone 6s and iPhone 6s Plus. No sooner had he brought them home and unboxed them than he’d dunked them in bowls of water to see if they could withstand being inundated with H2O.

Against the odds, it appears they can (for the most part). In the video above, you can see Straley submerge his iPhones for over an hour, during which they appear to function perfectly normally. Over the course of the water torture – or maybe it’s just a nice, relaxing dip, as the iPhones certainly don’t seem to mind too much – Straley tests the phones intermittently, checking specific functions like starting the Camera app and using the new 3D Touch feature.

Amazingly enough, everything works fine, with the phones seemingly exhibiting no damage whatsoever from having been immersed in liquid for more than 60 minutes – at least not yet.

In an updated video 48 hours later (see below), the phones still look remarkably good, with Straley demonstrating that features like the Touch ID fingerprint sensor and audio speaker were still operating normally.

However, as Straley points out, there is one particular “casualty” that presents itself after 48 hours: a thin diagonal line appears on the screen of the iPhone 6s, indicating that some degree of water damage has affected the smartphone’s display. It’s hard to make out, to be honest, but it’s still clearly a problem.

So it turns out that there are real-world consequences, no matter how minor, to letting your iPhones go skinny-dipping. Just try to keep your iPhone away from water, as whatever level of unannounced water-resistance Apple is implementing in its new models, they’re clearly not 100 percent waterproof yet – although we’re still pretty blown away by just how impervious they turn out to be.

Who knows, maybe full waterproofing could come in next year’s model? After all, Apple does hold a patent for that very thing.