Armor Cooler goes between your vest and your body to create air channels all the way down the interior of your vest. Heat rises and escapes out of the top of your body armor as cool air naturally replaces it. There are no moving parts, no batteries needed, no hoses or pumps or anything else to go wrong. If you’ve ever worn body armor and found yourself tugging on the front of your vest to let the hot air out, you’ll immediately fall in love with your U.S. Armor Cooler. The U.S> Armor Cooler simply creates air channels from the top of your chest down to your midsection to let all that hot air escape and be replaced by cool ambient air. Also, if you point a cold AC vent at your collar, the cold air will go all the way down the interior of your vest! Adding or removing a Vent-A-Vest cooler is extremely quick and easy. Simply position the Vent-A-Vest cooler behind your front vest panel, with the top edges about even. Then use the included straps to secure it to the hook-and-loop areas of your vest. It’s that easy! It works on hidden vests and external vests too!