Features: Make of stainless steel, this exhaust grille is strong and long terms. It effectively prevents fly and from entering the ventilation systems, a clean and hygienic environment. The flanges design provide a secure and easy installation on the exterior wall, a tight and firm connection. The slats designs allows for efficient air ventilation and prevents rainwater from entering the exhaust systems, protecting it from damage. The builted in check gate design allows for quick fog exhaust without backflow, effectively avoid the entry of fog and other unwanted. Specifications: Component: Stainless Steel Type: Suitable for 100 wall holes/Suitable for 150 wall holes/Suitable for 160 wall holes/Suitable for 180 wall holes/Suitable for 190 wall holes Size: As Shown in the Picture Package Includes: 1set Round Exhaust Grille note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color.