90mm fan cover

Fits a Duratech 90mm silent case fan from Jaycar. I like this fan because its very quiet.
4mm screw holes may be a little tight for M4, but gives M3 a bit of room to fit nice.
Clearance for 6mm screw heads.
0.5mm chamfer on all bottom edges to eliminate first layer squish.
Autodesk 123d file included if you want to change anything.