You're thinking of the MaxxAir fan cover.
The MaxxAir fan
is the same height as a Fantastic Fan when closed and no more obtrusive looking. Comes in white or smoke transluscent covers, manual or automatic with remote, thermostat settings and power lid.
The best benefit is that when closed, you don't see it but when open, you can use it in even heavy rain.......something the Fantastics can't do.
I have 2 of them on my 19CCD and with one pulling air in and the other pushing out........I very rarely need air conditioning.