Broan-NuTone DC4 Roof Vent Cap Duct Collar, No Size, No Color

this is basically a proprietary 4" collar. It's nothing special except that it twists into certain Broan 4" caps, and it doesn't even do that all that easily. It works and it's mildly convenient but it's ridiculously expensive for what it is, and even it were half the price I'm not sure that would be a great value either

This is a hard to find item. The roofer only installed the vent and I guess they took this critical part. Just glad I finally found it without having to buy the entire kit! Works as advertised and very easy to install

Excellent quality, THICK duct collar. Used this collar to install two Panasonic ventilation fans in my two home bathrooms. Perfect fit between this collar and the (Broan-Nutone 636) roof vent cap (also reviewed). The non-serrated end of this collar screws securely into the bottom of the roof cap with just a gentle twist. No rivets or screws needed. Other collars of similar type stocked at the two local BORGs were flimsy a-few-gauges thinner sheet metal. Go Broan-Nutone products, you won't regret it.

This was essentially impossible to install from inside the attic, after the roof had been installed. It would catch but couldn't be threaded around the hole in the vent. Since I blame the roofer, I only took off one star.

Perfect part to match our new bathroom Heater / Vent replacement. Can't ask for more.

Well made, good quality & easy installation

the part was exactly what I needed and fit perfectly

Screwed right into bottom of vent, that being said, the vent I used was also a Broan-Nutone. Not sure how well it would work with a different brand. Used a thick bead of silicon caullking where the collar meets the vent to prevent air leaks. Worked great.