Eliminates softening and jamming of your filament due to heat produced by the extruder motors. I also added heatsinks to the top of my motors.I had to print this with massive supports in the orientation it's already in. If anyone comes up with a better way let me know!Much credit and love to Lemm, whose original Printrbot fan cover design:http://www.thingiverse.com/thing:261115I crudely hacked in order to make this part.