These goggles have a special venting system designed to work functionally with the way you breathe. The mouth vents are located so you breathe and shout through the vents rather than into a large mass of plastic or rubber as with other goggle systems. As your breath hits the front of the mask, it either exits directly or is deflected sideways and outwards. There are specially shaped vents which take the deflected breath and move it out from the face plate. These specially shaped vents project your voice and warm breath out to the sides, and not up into the goggle. As your breathing warms the front of the mask, it heats up dry air in the demist guide. This demist guide is specially designed to prevent hot moist air from your breath getting through vents in the bottom of the goggle. Instead, the heat is transferred to dry air in the demist guide making it rise and move up across the lens of the goggle. As this air rises, it draws in fresh, dryer air from the back and sides of the goggle. This allows you to have a flow of air across the lens to help avoid fogging, while ensuring no moist air gets from your breath into the lens area.
