We provide 3 different s tandard hoods but also build custom designs to your specifications. To prevent air flow tunneling, the hoods have a horizontal filter, more charcoal (1.5" to 3" thick, TEDA-nuclear grade, 8 x 16 mesh), a higher air flow of 148 cfm fan free air, an auto shut off timer, a baffle that directs airflow to the rear of the hood, and a hinged face plate for extra flow protection. All of this is provided in units that cost less and require less space than similar hoods.