Exhaust Fan Flange 92mm to 75mm

This is basically just a part intended to connect a 92mm 12V fan to a 75mm diameter duct. It will act as a connecting part for my 3D printer enclosures exhaust.

The parts i am using:
Fan: http://www.pollin.de/shop/dt/NTc0OTc2OTk-/Bauelemente_Bauteile/Luefter/Axialluefter_SUNON_HA92251V4_999_92x92x25_mm_12_V_.html

Duct (75mm version): http://www.ebay.de/itm/300650466024