Product review (4 stars): Heartland dryer vent enclosure
This is a good dryer vent enclosure once installed. I had 2 issues with the installation.

The first is that the mating surfaces between the existing dryer vent in the wall of the house is the same size as the flange opening to the vent enclosure, both about 4 inches in diameter so you can't easily fit one into the other the 1/2" that is required. I suppose you could duct tape the two together, but it may be a little off and is a sloppy installation technique, at least to me. I went out and purchased a crimping tool from Malco at the Home Depot, crimped the dryer vent end from the house, and then joined it to the flange. This worked well.

The second issue, although not real serious, is that the six included screws were very short. Four of them worked fine in attaching the flange to the wood block I had up against the Hardy Plank siding, but I needed two much longer screws to attach the unit to the siding on the top of the vent enclosure.

The whole process took a little over an hour. There's no question this is a much more air tight installation then the old metal flapper I had installed and also should keep birds, vermin, and insects out as well. Time will tell.