I, like you probably, wondered what the heck this device did. Apparently it trains your lungs, allows them to fill with more air, work better, stronger, and faster, so essentially the Ironman PLUS is like a workout machine for your lungs.
There are three settings, light, medium, and heavy. Obviously you would probably want to start with the light level and work your way up. It is said to help with your breathing and even your breath-holding abilities.
Supposedly it can even help asthmatics by slowly decreasing the need for a preventative inhaler. For those of you not suffering from asthma, or for those who are more physically fit, it can also improve breathing efficiency, which should prevent the build up of that utterly painful Lactic acid that builds up when you are exercising but not breathing enough. There is also the obvious benefit for swimmers of not having to come up for air as often.
POWERbreathe Ironman PLUS [via coolest-gadgets]