Kair Connector with Backdraught Shutter 100mm - 4 inch Non-Return Damper Flap to Connect Duct Pipe or Flexible Ducting Hose

This works really well, it has a plastic lip half way down which you can shave a bit off to fit inside / in the middle of a 100mm tube. They're hard to get in stores for some reason, but it works really well, as soon as the fan starts it opens, then closes when it's off.

Good design and works at a good price

Returned as wasn't needed. But the quality looked good in the packaging.

Does the job very well

2 main problems: 1. The overall manufacturing quality of the product was not as I would have hoped. The plastic molding is poor with a jagged part jutting out of the flap in an area which could potentially interfere with it's closure. See photo. 2. I found that the flap does not swing freely even before being fitted, and there is some resistance even to gravity. If the product is compressed slightly from the outside then the flap does not swing at all and can be held in an open position. Considering that the movement of the flap will only get worse as the product inevitably collects dust and grime I elected not to fit this product and fitted a competitor product of the same mechanism which seemed immediately better quality and performance. N.B. I did bought a second one of these as I wondered if it was a blip but both were the same and were returned.

I bought this when I realised that our new home had a cold draft coming from the cooker hood when it was off. This was a lot of cold air costing money on my heating bill and not environmentally friendly at all! It fitted very easily and size selection was easy as the dimensions are in the photos with the description of the product. The best bit of this is that it uses gravity to close and the fan draft to open. It opens readily with almost instant reaction to switching on the hood even at the very lowest setting. However it does not bang or tap (like some do) when windy. The outlet gets a lot of wind hitting it as it faces west and is an open area prone to strong winds and there is no draft at all through this device. The second great thing is it has no spring due to gravity action for closing. Springs can be a real pain on these types of product so that is good. The only thing to remember is it only works mounted horizontally and get it the right way up! Overall its going to save me lots of cash in reduced heating and its environmentally good thing to do. For those that are interested the device uses offset hinges that have the larger area of the shutter (heavier side) causing the shutter to fall closed, when the fan starts the draft pushes the heavier side open by the small air pressure created and it opens fully. Very pleased with how well this balancing act is executed and can fully recommend. Don't forget to put some tape around any small gaps in the pipes when connecting the ducting to stop even the little drafts from the joints.

Fits perfectly

I bought this to stop draughts through the extractor duct, which caused the extractor fan to run for an extended period to clear the shower room. Works fine and immediately shows the difference in humidity reduction in the shower room. Only concern is that the build quality isn't great, so when you tighten the clips around the ducts, make sure the flap works freely.

Made of thin abs plastic. I thought they would be more durable for the price. If I didn't need them I would have returned them.

scarsa la tenuta in controflusso, nel mio caso ho risolto con serranda motorizzata con flap dotato di guarnizioni di tenuta ....... che ha ben altro costo rispetto a questa serranda di plastica. piuttosto che niente meglio piuttosto, ma non aspettativi chissà quali prestazioni, per quello che costano un tentativo fatelo, magari per le vostre esigenze sono sufficienti.

Fácil de instalar si el tubo es de las dimensiones adecuadas. En mi caso el tubo era un par de milímetros mayor y lo he colocado con un poco de cinta para fijar e impedir paso de aire. Lo he combinado con extractores que ya tenía y también en ventilación pasiva con el tubo en horizontal, va perfecto.

Very good

Schnelle Lieferung, Artikel wie gewünscht.