The Range Hood Damper Mounting Plate Features A 7" Diameter Opening. This Universal Accessory Is Designed To Be Used With Many Standard 30" And 36" Under-Cabinet Hood Models And Brands; Check Your Model Number To Confirm Compatibility. Installing This Accessory Will Require Basic Hand Tools, Some Disassembly Of The Range Hood And Novice Repair Experience. You Must Shut Off The House Circuit Breaker For The Appliance Before Installing This Part.