Product review (2 stars): look at another hood, not worth it
Not well made. Setup for ducted ventilation, the very weak cover provided  to seal the return when used for non ducted operation, bows and seals as well as screen door on a sub. The power switch for the light falls off because not enough threads for the nut to secure it to hood. Really not much quiter the the one it replaced (original cheap contractors brand).  Better off with an other brand. Wish I had taken my advice.