I wear a pretty typical neoprene mask in the winter, and only don the googles when it gets below about -30 degrees C (about -20 F) only because my eyes don't seem to get cold until about that temperature. I have only cycled down to about -35 (probably close to -45 with the wind chill), but even in a strong wind I never felt like I needed a heat exchange mask. Are you sure you need one? Is this a special needs case?