The big box stores carry a similar replacement unit in my area at half the cost but the tabs and electrical outlet cut out don’t quite align. This unit is of the same quality (pretty sure it’s the same manufacturer) but it fits like a glove. I upgraded the vent cover to the one that provides a light which you can find most anywhere. Very happy with the end result. Hoping both this fan and I last as long as the 30 year old original!