As part of my fume extraction system (see https://www.printables.com/model/427271-couplers-for-25-fume-extraction-hose ), I needed a way to connect 2.5" hose to an exhaust hood (Everbilt exhaust hood with pest guard, purchased at Home Depot or other big box stores).
I created this coupler that is used instead of the aluminum perforated tubing that comes with the exhaust hood. This coupling slips in the hood, over the tabs, and then rotates 45 degrees to keep it locked in tape. If you want to fix it in place you can use some aluminum foil tape (don't use ductape, that doesn't last).
The coupler comes as version with or without a built in screen. The guard that comes with the exhaust hood will keep pests like mice out, and is louvered, but if you want to also keep smaller critters out you can use the screened version. I would recommend the non-screened version if you don't have access for cleanout.
Printed in PETG on a Prusa MK3S
The author marked this model as their own original creation.