The stock PP3DP "wind barrier" for UP Plus, UP Plus2 and some similar printers (Afinia etc.) is ok for PLA but for ABS the air passing trough "closed flap" makes ABS prints warp. There's a nice upgrade [PP3DP Up Plus redesigned wind barrier](https://www.thingiverse.com/thing:253687) by PrintMo that I have bin using for years and that works like a charm for ABS. Now if you want to move away from ABS and go bit hotter and print PETG, PC, Nylon.. (all possible since we do have an all metal hotend here!) the small axial fan that cools the cold end of the extruder (the throat) is not enough and for too hot or very long prints you can have jams in the throat, underextrusion etc. This is why I redesigned the piece from cratch for a radial fan. Radial fan can push more air at higher speed then regular axial fan, they are easy to get (~5$ on ebay delivered) and they do not produce much more noise then the provided fan. You can even get some "super strong" ones that can push huge amount of air that you can slow down with 7809 or 7805 to get the quiet and still have huge amount of air going trough... I intentionally didn't add any mounting arms for the fan mount as I prefer to just use hot glue (hotsnot, hotmelt glue, whatever you call it) to link the duct and the fan. This way the hot glue seals the hole between duct and fan and provides some vibration dampening. It's still easy to remove fan from duct if need arises. The exit hole of the duct is projecting air at 30°-45° upwards so it does not interfere with the print. This part will not help you print with PLA or any other material that require part cooling! For that use the original pp3dp design and open the door to cool the part. and of course, sources are available on [onshape](https://cad.onshape.com/documents/891227d519d08c4114ea0009/w/790d96a37a8ac64342ee9d6c/e/c8da2c4b949dc5dfb5b37113)