Product review (5 stars): Just what's needed to close a dryer wall gap
Great invention. The previous reviewer comments were a big help. Trim with tin snips (very easy) and be sure to get the Scotch 3311 foil duct tape to cover all exposed seams. Alignment was easy for a first pass cut. As we aligned the resized unit, we noticed that the unit would have to tilt upwards slightly, so it was good that we hadn't made a precise cut on the first pass. Due to sloppy home construction, our wall vent sticks out about 4" from the wall, which prevented us from getting the dryer as close as we hoped to the wall. But it did close the gap a bit and we're very pleased with the product. Some reviewers commented that the thin gauge metal  implies a cheap product. But it's exactly what's needed to constrict air flow. Heavier gauge metal would be too difficult to work with.