This is an old Homart brand, sold by Sears, window exhaust fan. The motor was 2 speed but now it is only 1 speed, the low speed, the high speed windings are burnt up but it still works fine on the low speed. I took it apart, cleaned it up and repainted it. It has a new belt and cord. It measures about 27" wide x 23" tall so your window would need to open at least that big to fit the fan.
Asking $100.00