Vent Systems 4'' Inch (Opening Dimensions) Pack of 5 White Soffit Vent Cover - Plastic Round Air Vent Grille - Built-in Insect Screen - HVAC for Bathroom, Home, Kitchen 5.2" Inch (Outer Dimensions)

Works well. Used this to create vents on reptile tank. Great quality

Works for what I need.

As advertised. Would buy again.

Perfect fit for my custom engraving machine ventilation inlet

Worked great for flex duct for my crawl space dehumidifier.

Worked great

I needed to install vents in my backyard shed and this 5-pack fit the bill. They are simple, with fit louvers and an insect screen on the back, and well made. I did not realize that they had plastic plugs to cover the mounting screws, a nice touch. Screws not included as advertised but not a problem. I was going to buy stainless steel screws but with the cover plugs, ordinary common galvanized - which I had on hand - are fine.Followup: I was concerned about UV resistance and decided to paint them. Found a can of plastic-suitable spray paint that virtually matched the color, cut a mask out of chip board and sprayed them in place. Looks great!

Does not have sleve to adapt to duct