This is a cooling duct made for a Cetus3d printer that aims to improve cooling for both the areas before the hot zone and the part area below the nozzle. From what i've found this works for all nozzles included with the Cetus3d printer and should only direct air where its needed.

What you will need:
60x60x15mm 5V DC blower fan
https://www.amazon.com/gp/product/B01DA1BB8K/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

2 M3 6mm screws with nuts
1 M3 8mm screw
2 scotchlok connectors to connect blower fan

Installation

1. Remove the existing 40mm fan and cooling duct and clean up as needed.
2. Either attach a new jst connector to the 60mm blower fan or use the one from the 40mm fan using the scotchlok connectors. (make sure to give yourself some length to work with on the wires)
3. Slide the new cooling duct as shown in the above images. (you do not need to remove the nozzle for this)
4. Screw in all three m3 screws to secure the cooling duct.
5. Attach the 60mm blower fan to the duct and use the screws that were included with it.