Automatic Gable Shutter, White, Louvers Open Outside When Gable Fan Is Running, Louvers Close When Gable Fan Shuts Off, Made Of Plastic To Prevent Rust, Rough Opening Is 16" x 17-3/4", To Be Used With Model #'s 53315, 53316, 53319 & 53320. This shutter is for a gable mounted power fan. The louvers automatically open when the fan runs and close when the fan shuts off. The louvers are white and can be painted to match the exterior of your home. They are also made of plastic to prevent rust. The rough opening is 16" x 17-3/4". This shutter is made to be used with model numbers 53315, 53319 & 53320. Automatically opens when fan runs Can be painted to match homes exterior Shutter for gable mount power fans