Review on iPower 12-Inch Square Silver Aluminum Automatic Gravity Shutter Louver Vent by Djkutt Kent

It is advertised as weatherproof and pest proof. That's not even remotely true. There is 3/8 inch spacing on either side of the louvers and 1/2 inch spacing on the top. You can literally see through it on the outside. If you install it in a cold climate, your heater will be on all the time because you'll lose all your heat as a result. If you were hoping to keep bugs out of your building after dark, forget it. You have to keep the exhaust fan on or they'll swarm through those cracks as soon as you turn on the lights. Look for something better.