Product review (5 stars): BEFORE you try to install this great vent....
The Lambro dryer Vent is a wonderful device.

When you are replacing a dryer vent with the Lambro dryer vent you must make some arrangement for securing your flexible vent pipe coming from the dryer onto the outside of the house.

The directions on the box leave something to be desired.
The directions (Step 1) ASSUME that the existing dryer vent pipe is secured to the outside of the house before installing the elbow section.

My former metal dryer vent was something like this with the flexible pipe stretched over the inside end of the metal pipe and clamped over it.
When I removed clamp holding the flexible pipe and pulled the flexible pipe off from the metal vent I realized that there was nothing to secure the flexible pipe to the outer house wall!
  So I cut off the metal hood on my old vent to leave a flat, square outer surface. Next, I reattached the flexible pipe and clamp and pushed it back into the outer house wall. Then I caulked around the metal pipe where it goes through the clapboards. I also caulked the outside face of the old metal dryer vent (now missing its hood).

(Step 2) I placed the elbow section the metal surface (covered with caulk) and screwed them into the outside wall. This way I had a sealed, secure way of connecting the flexible pipe and the new elbow section.

(Step 3) I completed  installing the upper section and it worked like a charm. The cold dryer and room around it are now cozy!

When you are replacing a dryer vent with the Lambro dryer vent you must make some arrangement for securing your flexible vent pipe coming from the dryer onto the outside of the house.