Suitable for most turbine ventilators: The roof ventilator cover measures 20 inches x 20 inches. Please verify the dimensions of your turbine fan before purchase. Protection function: Once installed, the roof ventilation cover protects the turbine from rain, snow, wind, and dust, helping to maintain a clean indoor environment. Hygienic environment: Helps prevent heat loss by reducing indoor temperature. Waterproof and dust-proof: The roof ventilation hood is made of polyester with a silver-coated interior for effective waterproofing and dust protection. Easy to install: The bottom of the roof vent cover features a drawcord. Tighten the cord to secure the cover and prevent it from being blown away by strong winds. Color: Black Material: Polyester Size: 51 x 51 cm Package Contents: 2 x Vent Cover or 4 x Vent Cover Note: The package includes only the items listed above. Other products are not included. Note: Lighting and display differences may cause slight color variations between the image and the actual item. Measurement error allowance is +/- 1-3 cm.