THE ONLY SOLUTION IN BODY ARMOR VENTILATION!   Tac Vent 2.0 was designed and produced by an active duty law enforcement officer to cool you in your armor by 7-14 degrees!  The Tac Vent woks with inner armor (under a uniform shirt) or with an outer carrier, just place it behind your armor and immediately notice the difference!  In addition to the cooling benefit of Tac Vent, you will also experience a significant reduction in blunt force trauma should you ever be subjected to a bullet strike (obviously always use the Tac Vent in conjunction with your body armor as Tac Vent is NOT ballistic).   To install your Tac Vent, place it between your inner shirt and your body armor with the holes facing your body, there are an additional set of holes on the ridges designed to allow you to zip-tie the Tac Vent to an outer carrier as well.   Buy 1 for $39.99 or 2 for $64.98 and save to have front AND back cooling and blunt force trauma mitigation!