You probably have been snorkeling at some time in your life. And you have probably experienced many of the undesirable features of snorkeling: fogging masks and constant water in your snorkel / mouth. Well, all that can be quickly and inexpensively changed with an Ocean Reef Aria Snorkel Mask.
The Aria was uniquely designed and developed by Ocean Reef, an industry leader in the manufacturing of masks. With the snorkel attached above the forehead, the Aria allows fresh air to enter the mask from the top and through special 1-way valves on the nose port the fresh air is easily inhaled--through either your nose or mouth. When exhaled, the air leaves the mask through the purge valve in the bottom. This constant circulation of air keeps the mask from becoming fogged. In addition, with nothing in your mouth there is no jaw fatigue and it is nearly impossible for you to ever have pool or ocean water in your mouth. You can even easily snorkel with contact lenses or use self-adhesive lenses available from most dive shops.
Many dive shops and tour operators in Cancun, Cozumel and Isla Mujeres have the Ocean Reef Aria Snorkel Mask available for renting and purchase. BEWARE: There are inferior imitators that leak and fog-up. If it isn't an Ocean Reef mask then it is a cheap imitation.