Twin version, with two double inlet wheels on the same shaft and three bearings or, in sizes from 710 to 1000.  Version supported on strong rectangular side frames, made of hot rolled steel sections, fixed on the scroll sides with screws, available from the size 250 up to the size 1000.  Single row ball bearings on cast iron pillow blocks with grease points.
The standard fan can be freely rotated, to allow installation with orientation 0, 90, 180 or 270, as defined in Eurovent 1/1.
