Product review (5 stars): Great solution for dryer venting
Item was purchased based on previous reviews and I was not disappointed.  Vent closure is very well made,sturdy,and parts fit and work perfectly.
  Mine had to be mounted over aluminum siding so I screwed the vent closure parts onto a piece of 3/4"X8"X12" painted board with a 4" hole in it for the duct pipe.  The painted board was then attached with 4 long screws through the siding.  Worked very well.
A bit of silicone seal to get everything airtight and we now have  a much warmer laundry room.