The FRI-191022 is built for outdoor applications. The cabinet is rustproof, tamperproof, weatherproof, all aluminum construction and fully insulated with ROXUL RHF40. All surfaces are made of double wall aluminum with an insulation of 1" for the walls and the roof. The insulation (on 6 surfaces) has the benefit of keeping the heat in the cabinet in cold weather as well as keeping the heat out in summer. This insulation also creates a physical wall protection against internal condensation. The door is lockable, insulated and sealed with a compression rubber gasket. Behind its locked door, rack mount accessories can be secured to standard 19'' rails. Six 10-32 screws are provided to fix rack mount devices to rails. (2x) knock out are available under and (2x) knock out are available on the back of the housing. A blower insure good air flow (100 CFM) through the cabinet during warm temperature with a filtered air input. The blower and heater (optional) operate when the heat reach a preselected internal temperature which is controlled by a thermostat.