Backdraft Damper Flap Assembly Part-(3 1/4 x 10

Backdraft damper flap assembly (specifically sized 3 ¼ inches by 10 inches), which is commonly used in kitchen range hoods or over-the-range microwave exhaust ventilation systems. Product Details: • Prevents Backdrafts: The spring-loaded or gravity-assisted metal flap opens when your range hood fan is turned on to let cooking exhaust escape, and swings closed when the fan is off to prevent cold outside air, wind, insects, or odors from entering your home. • Protective Film and Foam: The blue plastic is a temporary protective film to keep the metal from getting scratched during manufacturing and shipping. The white styrofoam block inside is packaging material used to hold the delicate swinging flap securely in place so it doesn't bend or warp before installation. Important Installation Steps: 1. Peel off the blue protective film completely before installing the unit. 2. Remove the white foam insert from inside the frame. If you leave it inside, the damper flap will be blocked and won't open, preventing your fan from venting properly.