Replacement Vestal Damper Plate 42" - For old, rusty, warped or missing damper plates we have replacement Vestal Damper Plates. It doesn't matter if the old Vestal Damper has poker or rotary controls - In a matter of minutes you can easily slide out the defective plate and slide in a replacement plate. The large hole in the damper allows installation of a rotary control. The smaller hole is used to run a wire through and fasten the damper controls to the damper body.