The fan I had on the original bracket was way too loud, so I replaced it with the type of fan that comes with the Prusa i3 MK2.

https://www.amazon.com/gp/product/B00MJU6JR2/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

I printed this with PETG, but I don't think the material should matter. There is a relatively small gap for the small fan, but it works great. I am printing PETG at 245C with this and am having no issues.