The Subzero Warm Breath Mask
This is the fleece mask preferred by high-altitude mountaineers and Antarctic scientists because it humidifies and warms winter air for comfortable breathing. A special ventilation chamber lets wearers inhale full, unhindered breaths while trapping a small amount of heated, humid exhalation. The result is a comfortable, fully oxygenated “microclimate” inside the mask with up to 80 percent humidity and temperatures 40° F to 60° F warmer than outside air.