Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White

I've being looking for a coupling that fits perfectly on my dryer vent and I found with this backlog flapper.

No gaskets or o-rings to help seal, but should stop most back draft. Here is a much better one: AC Infinity 4" Backdraft Damper, One-Way Airflow Ducting Insert with Spring-Loaded Folding Blades for 4” Ducting in Range Hoods and Bathrooms Fans https://a.co/d/hodpLQl I used this one in a corner just above the room and the better one at the outside wall. Fits nicely into a 4" 90.

Fit a 4" bath vent with no issues

Nice damper for 4 inch metal ducting, used it to isolate the existing dryer exhaust duct, from an ad hoc fan driven exhaust to vent my cat’s sealed litter box cabinet. Must install vertically. The existing dryer flow creates outward suction which seals the damper so there is no backdraft towards the newly installed fan exhaust ( very necessary to minimize lint to build up). When the fan is in operation ( with or without the counter dryer suction) the damper opens up and allows the stink to vacate my basement.. just what I needed...( the damper is installed between the t-shaped duct and the flexible piping in the picture)

I have been searching for some kind of 'automatic one way' check valve to install on a 4" air ventilation line. It needs to open with the relatively low air pressure provided by inline duct fans and shut completely when the fan is off. In my case this just did not work. It will open under the pressure of an inline fan but even when the fan is off it opens under the natural draft as colder air wants to move in through the fan as well. That might work for some applications but not what I needed. The flapper does seem to swing open and shut whether mounted horizontally or vertically. While I did not expect the flapper to be of heavy material I was surprised by how thin and light the body of the unit was. The housing on the flapper valve does appear to be pretty flimsy.

works great

It worked, it fit, and should work good long term for my purposes.

Product material is sub-standard, broke and chipped easily

Ottimo prodotto

Wanting to replace two rubbish "Silavent" ceiling extractor fans with inline fans, I needed to source to vents with shutters, but none were available. So I bought two KAIR vents and two of these. They fit standard 4" (100mm) solid or flexible duct pipe. These are unsprung gravity flaps, so they need to be fitted nothing but vertically to operate properly. Fitted any other way and they won't close. They are also best fitted at the vent in the ceiling so they become dual purpose backdraught and odour eliminators. They seem good quality and due to them not having springs, there's nothing to go rusty and stop working.

Facile d'installation, efficace et pas cher

Deze terugslagklep heb ik gebruikt voor afdichten van afvoer van dampen douche in badkamer deze staat achter de ventilator bij de vorig ging de klep nog geen 1/4 open om dat deze te veel weerstand had deze gaat met zelfde ventilator meer de dan half open werkt perfect en sluit goed af.

Gut und preiswert.