I would not discount the new
Fan Mate with the large cotter pin type clips.
I had the old 850 and while nice the thumb screws that you twist off to open,like this
Galled on me after only 2 years. I had to cut them off to get the cover to open.
I replaced it with the new Fan Mate,it has the same Six-Year Limited Warranty, it is taller in the rear so the fancover opens more to give more air flow, and with the clips it is easy to open to clean.
Mine has been on for 5 years in the California sun and looks and functions as new.The old one still sits in my storage shed.
