[Gasoline Fumes]

These vents have a pair of plastic shutters that are actuated by a small DC motor. Perfect for an automated grill block! But being a motor, they need only a short electrical pulse to move. You can't feed them continuous power. The timer takes 2 AAA batteries, so I assume the motor gets about 3 volts. It works fine on 1.2v. I wouldn't try 12v! Some weatherproofing for the motor will be necessary. The shutter area is about 4" x 9". I'll try one first, maybe that'll be enough airflow. I usually have a smaller grill opening than that.

I bought a bunch. I'll make a post in the classifieds if anybody else wants to play with one. Or if you're in Upstate NY, look for Real Deals Dollar Stores!