Product review (1 stars): It works as advertized and I was satisfied with the product until now
Purchased this vent in 2012, it works as advertized and I was satisfied with the product until now.  It requires cleaning about every 6 months, which is not a big problem, but be aware it will clog up.  However after being installed for only 2 years, the plastic became very brittle, and while trying to clean it, the unit shattered into about 20 pieces.  It is a good product if you don't mind replacing it every 2 years.  The sun's UV rays have migrated the plasticizers out of the base plastic, leaving it extremely brittle.  However, I will not replace it with any plastic vent.  I purchased a galvanized vent to replace it, which will last much longer.