The winter apparel company NuDown has developed a new way to stay warm during the winter while permitting variable temperatures. After all, you may want to wear a parka while walking through -10°F temperatures outside. But once you're indoors, the parka becomes way too hot to wear.
NuDown's jackets are inflatable with a hand pump that stores in a side pocket. Just pump in air to increase the insulation inside the jacket. Then release it for warmer environments. Fast Co Design reports:
The jackets are each fitted with a pump that you inflate when you need to—instead of throwing on more bulky layers, just add air. NuDown says 20 pumps will add enough insulation to keep out the chill on chilly days, 30 pumps will give wearers more warmth on blustery days, and 40 or more is supposedly enough for the harshest conditions (the company gives the example of waiting on a windy ski lift). If the coat gets too toasty, deflate it to cool down.
Each pump supposedly adds one degree Fahrenheit of comfort, but for temps dipping below 20 degrees Fahrenheit, NuDown recommends using its Argon Gas Upgrade kit. The add-on will inject your coat with argon, the same gas that's used in double-pane windows and dry suits, since argon is better at insulating than air.