Product review (3 stars): Well made. Specifications unclear.
A nasty wind storm took out my 5 year old vent. I measured the old one and found it to be 8" side to side and top to bottom. The diameter of the vent tube was 6". So I ordered the 8" size. Wrong. The 8" refers to the tube it fits not the dimensions of the louvers. It was not worth the cost of shipping it back. I sure wish the vendor would supply a complete set of specifications. It would prevent wasted time, money and effort.