The Holmes model will either pull in air from the outside with both blades, or it will exhaust air with both fans. $25.
The Midea model (all white) has a side fin to block the remainder of the opening on one side, but will usually stretch the full length of a normal window. Both blades can pull in or exhaust. $20.
I accept cash. No virtual money. Fans can be picked up in Herman (East Butler).
Seventwofour-3five5-7zero3zero. Call or text. If you email, I may not respond for a few days.