This is the one I just purchased and installed on my Axis. The reason I selected it is because it is deigned for the fan in my 2016 Axis. Installation entails screwing in 8 #6 screws into holes that are already in the side of the fan, attaching the brackets. Then it is two bolts and two clips to attach the cover. No drilling, no holes in the roof, took 5 minutes - during my twice yearly roof inspection. Two clips are easily removed and the cover opens for cleaning underneath it.
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