This is a 40mm Pivoting Fan Mount that attaches to the side of a Printrbot Plus.

This 40mm pivoting fan mount attaches to the side of a Printrbot Plus, over the right-hand smooth-rod enclosure. You may be able to use the existing screws with this part, but if they're too short, you can use 2x 1-3/4 in. #6-32 screws.