This is a dual Fan duct that directly mounts were the original Fan mounted.
My printer is a Reprap Prusa Sunhokey 2015 model. I have since replaced the extruder with a new clone that was slightly short the original. Finding a good dual fan duct that directed the air exactly were needed was a challenge. This Bracket and duct assembly is adjustable all 3 axis
The bracket is mounted to the frame and can shift in the x direction. The ducts can be adjusted in both y and z axis to allow for precise direction of the air flow.
Standard 40mm 12 V laptop fans were used. you will need two and wire them in parallel. After bolting them on I wrapped the fan ducts in foil tape to prevent them from sticking to the extruder if they were to jambed against a warped part.
Printing with supports not recommended as its very hard to get them out after printing!