Product review (2 stars): ... too light and when the wind blows it can easily flip the louver up
The plastic is too light and when the wind blows it can easily flip the louver up. The worst part is the louver gets stuck in the up position providing access to rain or birds etc to enter. I might try to glue some small weights on the inside of the louvers to help prevent the problem. Naturally the vent is on the second floor so it requires getting the ladder out again.