Customized version of https://www.thingiverse.com/thing:2193701

Created with Customizer! https://www.thingiverse.com/apps/customizer/run?thing_id=2193701

Using the following options:

flange_gasket_only = 0
flange_gasket_thickness = 1
pipe_wall_thickness = 2
pipe_od = 106
pipe_length = 30
transition_length = 15
fan_wall_thickness = 2.5
fan_round_od = 103.7
fan_square_od = 92
plate_thickness = 3.0
plate_corner_fillet_radius = 2.5
fillet_fudge_factor = .01
screw_hole_spacing = 83
screw_hole_diameter = 5
arc_fragment_angle = 1
arc_fragment_size = .30