This uses a 80mm fan (attached to one of the rods of the printer) attaches to the cooling duct with a vacuum hose. All parts where printed with PLA.Tabs are in place of the 2 small plates for holding in the belt. I have yet to experience any heat problems; this may be due to the vortexing of air that, according to the simulation, happens between the fan duct, and the nozzle (the simulation did have a model of the nozzle, it is omitted in the picture) keeping the plastic cool. Designed around 3dstuffmaker's prusa. Also has better airflow! EDIT: This model works for j-Heads up to MkIV. was able to make it work with the MkV by using longer bolts. The torrent of air (showed in the airflow model) that occurs between the vent, head, and the carriage are noticable and should (hopefully) be enough to cool it when using PLA STL Repair http://cloud.netfabb.com/