Nicro Ventilations Air Vent 500 is wind-powered and easy to install. The engineers at Nicro Ventilation created a passive wind-powered vent that moves 600- 1000 cubic feet of air an hour with just a 15-knot breeze! This makes for an easy to use system with no cords and little maintenance. A locking, shut-off damper may be operated from below. Key Features Wind-powered Durable white plastic housing Screws directly to the deck Uses standard 3" hole Allows the use of Nicro trim rings Specifications Type: Passive Cutout Size: 3” Dimensions: 2”H x 7”dia.