Fantech FC 4 Mounting Clamps, 4" Duct

I used these mounting clamps at both input and outlet ends of a Fantech dryer booster fan mounted in a horizontal position. What I didn’t like was that the clamps seemed a bit undersized in diameter for the 4” aluminum ducts I connected to the fan, resulting in a bit of a crimp to the ducts causing slight air leakage where the bolts on the clamps fasten together. I ended up applying aluminum tape between the ducts and the fan before applying the clamps. In spite of this, the clamps were usable and will be removable to allow dryer vent duct cleaning from both ends of the fan after removal of the foil tape.

i need this and couldnt get anyone else to get a similar item to me on time , but this is really high priced .

Really nice quality. Expensive but couldn't find 4in clamps anywhere else.

easy to install simplifies, fan removal for cleaning.

Too large in diameter. Doesn't create airtight seal despite clamping all the way down and trying it on two different fans.

Installed easy and work great

Installation was simply. Sealed perfectly and did not require taped as a backup sealing.

Works as expected

Excellent clamps, FYI there are 2 clamps in each box. Give nice support for inlet and outlet ducts on DBF4XL Fantech unit. Found it difficult to align clamps when tightening due to short duct stub on fan unit approx 1/2 " sticking out had to fix ductwork with retaining screws so that incoming duct would not twist off when tightening clamp to seal.

Great product, really easy to install. The only problem is that is is quite pricy. But overall it's very good quality