... 4)low noise,big wind volume Series of Cone exhaust fan features:1) Reasonable cone designing, low noise, big air flow, strong ... nibreaking, aesthetic durability.6) There are two types of fan house, slant wall type, upright wall type, could satisfy ... )Width(mm)Thick(mm)XL-1100100060014003250075038011001100450XL-13801250439140044000110038013801380450 cone ventilation fan for greenhouse and poultry house