When combined with a Louvered Filter Fan Kit or an LFG series snap-on, slide or hinged louvered guard, Orion Fans’ specialty air filters offer low pressure drop, water resistance, fire protection, and the ability to capture large amounts of airborne dust in industrial enclosure applications. They are ideal for equipment where permanent, cleanable filters are most appropriate. The FHD Series (High Density), FHDH Series (Water Resistant) and FHDP Series (Fire Protection) are the ultimate filtration solution in networking and communications equipment where compliance to NEBS, ATCA and other industrial computer specifications are required. These filters also meet MERV rating for HVAC and air handling applications.