The EXHAUSTO BESF Box Ventilator is an efficient and highly reliable enclosed in-line fan designed to be used for residential kitchen hood exhaust, indoor air ventilation, or for residential or commercial combustion air supply. It also offers low noise levels, low energy consumption, a variable speed motor, compact design, low maintenance requirements, and minimal long-term operational costs. It can be installed in an attic, garage, or basement, or wherever convenient (indoor only) and capacities are available from 500 to 5000+ CFM.    The BESF's features include:   Totally enclosed, maintenance free, variable speed motor with permanently lubricated and sealed ball bearings and thermal overload protection.   Direct drive (no more broken belts!) stainless steel impeller with permanently attached balancing weights to reduce vibration (without further adjustments during installation or later in the field).   Lockable hinged service door for easy access to motor and impeller for cleaning and service (to maintain optimal operation, yearly inspection and cleaning are strongly recommended).   Corrosion-resistant galvanized steel housing insulated with 1¼" fiberglass mats is totally insulated against sound and corrosion.   For use with residential kitchen hood or downdraft exhaust systems, see the EXHAUSTO Kitchen Exhaust Brochure. The BESF is also suitable for the lint-laden air exhausted from commercial clothes drying operations (i.e., laundromats or hotel laundries) and for combustion air supply systems. For details, see the EXHAUSTO MDVS Mechanical Dryer Venting System or the EXHAUSTO MCAS Mechanical Combustion Air Supply System.   Tested and listed to Underwriter's Laboratories UL705 standard for power ventilators. Two year factory warranty; ten year warranty against corrosion perforation.   Product Information   Installation Manual