Product review (3 stars): Not so great on the 0-6 inch part without modification
I bought this online as I needed something with about a 4-inch height and no solutions were available at the local hardware store. The problem with this design, as you can see, is when you adjust to the lower heights, the extra length you're sliding out the bottom adds to the minimum height requirement from the floor, and this action pushed the vent too high to secure to the rear of the dryer. The modification was simple enough - I only had to cut off the extra length with a heavy-duty scissors, but this resulted in a jagged bottom edge during adjustment. I don't really see how they can claim it will work for 0-6 inches as shipped, and they should instead offer maybe a 0-6, 6-12, 12-18 inch selection. Not sure if this is Amazon not stocking the items or Whirlpool not carrying them, but different sizes sure would be useful.