Features: brand new high quality The joint is made of galvanized iron material, which is anti-corrosion, cold-resistant, high-temperature resistant, not easy to deform, and . The connector base has screw mounting holes, no need to drill holes, and it can be directly fixed on the wall with screws, which is convenient to use. The smooth for of the ventilation flange is convenient for connecting the air duct. Pipe flanges are widely used in ventilation s in homes, kitchens, bathrooms, garages and factories, etc. Product parameters: color: gray Material: galvanized iron Interface outer diameter: 73 mm/2.9 inches Diagonal Mounting Hole Distance: 88mm/3.5in Distance between adjacent mounting holes: 43mm/1.7in Base Outer Diameter: 98mm/3.9in Instructions: Screw the flange securely to the air inlet, air outlet, wall, ceiling or other for to connect to the ventilation . Note: 1. Please pay attention to choose the appropriate connection outer diameter before placing an order. 2. Screws are not included in the package. Package Included: 1 * pipe connector Note: 1.The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2.Please allow slight manual measurement deviation for the data.