calimaeroVKE 4" Inch Dryer Vent Cover – Outdoor Stainless Steel Grille with Moving Flaps – Fits Only with Metal Ducts for HVAC & Dryer Systems

It’s a very nice well put together stainless steel louvered cover

nice replacement for the old sun rotted plastic covers for the bathroom fan ceiling vents.

I ordered this product because the Calimaero is one of Bob Vila's top picks according to the small amount of research I did. This is considered a highly ranked product, and I'd say that overall, the quality is fantastic. I think this thing is really going to work for us for years to come; but, the sound!we have a relatively short dryer exhaust from our laundry area and when the air from the dryer pushes through the vent it lifts those flaps, but they don't stay up during this process. Instead they "flap flap flap flap flap". It sounds like a train rolling down the tracks!It's really very minimal and not something I would call a deal breaker by any means. The product itself is clearly of a high build quality and I'm overall very happy with my purchase. Had I known about the sound going into it though, I may have looked at other options.

Fit 4" vent pipe well. Like the fact it is stainless

The fit of this vent is perfect..! It's made of stainless steel, so it's never going to rust. Louvers close tight. Some on here have complained about the clicking of the louvers. Not a problem for me..! I wanted this to keep mice and vermin out. If you follow the directions, it's a 15 minute install..!

If you're looking to vent a 6" ducting run, this is absolutely NOT the wall unit you want. All of the rigid ducting (and flexible ducting) in your run has a 6" ID (+/- an eight of an inch or so). The area of your 6" diameter duct is 3.1416 x 3 x 3 = 28.27 sq. in. This wall-vent unit has such a restricted collar (5 1/4" dia) that it yields only an area of 21.65 sq. in. That's nearly 25% less that the area of your ducting run. And it's such an abrupt change (where your 6" ducting run meets the 5-1/4" duct collar of this unit) it creates measurable turbulence at that union... even if you cover it with metalic duct tape. That turbulence reduces the airflow by another 10% or so.Bottom line is a 1/3rd reduction in airflow. If you think that isn't going to affect your expected ventilation stream, you're sadly mistaken. You could actually damage the air conditioner (or whatever) you're trying to vent through your outside wall.DON'T WASTE YOUR MONEY ON THIS UNIT. Get one that has an actual ID as close to 6" as possible. Not this 5-1/4" diameter piece of Chinese crap.

I hope this lasts longer. The plastic ones in the sun last only a year or two. After 3 years they turn to chalk. These cannot be any worse.Better yet, they have spring clips on the outside. My 4" vent pipe is permanently installed. I cannot fit anything over the outside. The plastic ones now available are meant to go over the outside. Years ago they went on the inside. To use a new one I have to cut it off flush. This one fits inside perfectly.The only thing I do not like is the fins are very light and flutter. They make a lot of noise. I hope this does not shorten the life.Update: It did last longer than the plastic ones. I cleaned it several times. The last time I bent the fins. As noted, before they are very thin. Probably my fault they got damaged. Also, it never did really quiet down until it got mostly plugged.

Vent does its job really well. Keeps birds and creatures outside, and allows my dryer to do its thing. Sadly I had to dock points for just how NOISY this thing is. It rattles and rattles and rattles when someone is doing laundry. I can literally hear it rattling away a half a block down my street. In addition the flaps are so loose that it even rattles and makes a racket when a strong wind gusts, and during a storm I can literally hear the flaps flapping away which likely means water is getting in to the vent. It is installed up on a third floor though, so I can't easily swap it out, I just have to hope the water damage is minimal and that it is able to dry out after storms...