The Honeywell F70C is a self contained electronic air cleaner. It is ceiling-mounted and is used to remove airborne contaminants such as tobacco and cooking smoke, dust, and pollen. It surface mounts in a 2 foot x 2 foot ceiling tile or half of a 2x4' ceiling tile. The Honeywell F70C has a built in fan system that moves 1250 CFM so it does not need to connected to ductwork.