Powerbreather is a sealed snorkel for swimmers
The Powerbreather is an advanced breathing system for swimmers, designed to decrease apprehension in beginners and increase focus and performance among advanced swimmers. Essentially a sealed, watertight snorkel, the device gives swimmers a more natural way of breathing.
The device is quite simple. It has an intake valve located on the back of the head that allows the swimmer to take in fresh air while a second valve pumps exhaled air completely out. The swimmer enjoys more natural breathing without the need to turn his nose and mouth out of the water. The device is designed to keep all water out, so that breathing remains unimpeded. It fits any head size thanks to its adjustable hardware.
The Powerbreather offers a few distinct advantages over the traditional forms of in-water breathing, as explained on its website. By eliminating the need to turn and breathe, it reduces strain on the neck and shoulders. Since you don't have to turn your head, you can focus all your energy on developing proper form and technique. While the company doesn't come out and say it, it seems like the elimination of head movement and extra concentration on your stroke would also help you to swim faster and longer. Powerbreather is also billed as a way of quelling the apprehension of new swimmers, as it allows for more natural breathing without the worry of choking on water.
Despite how hard Powerbreather tries to sell us on the cool and fashionable aspect of the device, it's not-so-arguably pretty strange and geeky, and you're going to get some looks if you strut around the beach with it on your head ... but since when has anything in swimming (read: skintight trunks and swim caps) been about looking natural or stylish? Since never. Assuming it works, it could be a useful tool for the sport.
One aspect of the breather we do question is that it's billed as a useful training tool. We assume that such a device would be universally banned from all but the most casual swim meets and competitions, so it seems like training with a completely different motion (e.g. no head movement) than you're competing with could be harmful as opposed to helpful. Then again, we're not swim coaches, so maybe we're talking completely out of school.
Take an animated look in the video below.