These are the STLs you will need to install our 50mm blower fans to our printers. Please download the correct STL for which printer you own (Play, Simple, Plus). These are designed for our current lineup. * Just included the STL for the Simple Pro blower fan shroud If you need to purchase the 50mm blower fan you can find it on our site - https://printrbot.com/shop/fan/. Use 3/4" Phillips Drive Pan Head screws to mount the fan to the printable shroud We designed these files in Fusion360. You can find and alter/improve these files here - http://a360.co/2jRWJlk. Happy Printing from Team PB!