The file '30mm Fan Guard With Anti-backwash 3D Printer Model' is (stl) file type, size is 2.5MB.
A fan guard (for the inlet side) with anti-backwash blades for 30mm fans. Helps prevent air spilling where it shouldn't.
I use these for the fan on the extruder heat break with these fans
http://www.aliexpress.com/item/2-Pieces-Lot-12V-2pin-30mm-x-10mm-Mini-Small-Brushless-DC-Cooling-Fan/32335064214.html
