The FINIS Swimmer's Snorkel is designed to allow swimmers to concentrate on body balance, head position and stroke technique by eliminating the breathing cycle rotation. Breathing through a snorkel while swimming increases the capacity of the lungs to expel air required for optimal intake of oxygen. Regular snorkel training helps to increase C02 tolerance and V02 max.
Contrary to one of the above reviews, this item was available at my local store, twice. I had been using a regular mask/snorkel combo for my pool swimming, but noticed I was getting a crick in my neck after swimming for an hour. When I changed to this item, I no longer had that problem. I have MS, so I do have some problem with flooding, but I believe that is due to muscle weakness in my face. I love this item!