While AT&T may want to have nothing to do with the new HTC 10, T-Mobile seems more than happy to offer its customers a chance to buy the Taiwanese company's latest flagship smartphone. T-Mobile is going to start taking orders for the HTC 10 soon, but until that happens the 'un-carrier' decided to do an unboxing of the new device. This isn't your usual unboxing, though. Far from it. In fact, it's following the same idea as the one T-Mobile did for the Samsung Galaxy S7 and S7 edge - that is, make it extreme. Samsung's phones were unboxed underwater, so in TMo's logic it makes perfect sense...
Source: http://www.gsmarena.com/tmobile_unboxes_the_htc_10_at_10000_feet-news-17744.php