This part is a fan shroud for the Printrbot Simple. It eliminates the "bulky" side-mount wood piece and also the flimsy fold-up shroud that they provide. See instruction tab for more information.

I remixed this from user KAMIKAZEFREAK. Thanks my friend!

Assemble the fan to the shroud using three M3 x 10mm screws. Center the shroud to the extruder nozzle and mark the hole remaining in the fan. Drill a 3mm hole through the wooden Y-carriage and fasten using an M3 x 16mm screw and nut.

Once everything is aligned, you may need to trim the end of the shroud a bit.