Broan-NuTone ERV90HCS Energy Recovery. This unit is manufactured by Broan and offers a flow rating of 45-99 CFM (cubic feet per minute). The construction of the fan also has multiple side ports which allow the fan to easily remove stale air and replace it with fresh air in the room. The fan also offers easy to reach filters that are washable. The filters help to filter out particles such as lint, mold spores, pet dander and dust while protecting the fan from dust build-up. Great for homes in humid climates up to 3,500 feet.