The Large STEGO FF 018 is a high air flow (11x11 inch opening), low noise, and easy mounting filter fan assembly. The self-adhesive seal of the mounting frame prevents dust and water from entering the cabinet. The unit is comprised of four individual fan units that provide significant redundancy in the event of a single fan failure, ensuring electronic components stay cool. The functional design of the intake and exhaust fan hoods very effectively prevents direct infiltration of falling water and dust. Air channeling makes the filter fan particularly quiet in operation. This product is CE, UL Recognized and RoHS compliant.