AEROSTAR® 400-series pleated air filter with standard capacity achieves MERV 8. It utilizes a state-of-the-art 100% synthetic media to achieve exceptionally high levels of efficiency with the lowest resistance to air flow available. The media is laminated to an expanded metal grid on the air exiting side to provide exceptional strength during installation. The media support grid prevents fluttering and maintains pleat uniformity for optimum performance. The filter pack is enclosed in a heavy-duty, moisture resistant die-cut frame that will not warp, crack or distort under normal operating conditions. Designed for use in commercial buildings, hotels, industrial filtration, airports, school and universities or any application desiring higher levels of air filtration to protect occupants from airborne irritants and protect cooling coils, ductwork and other components of the HVAC system from dust and dirt.