Designed for general air filtration applications with light to medium dust loading conditions, HeavyDuty disposable panel filters are engineered for sturdy, economical performance and ease of use. The expanded metal support and skin provide excellent, corrosion-resistant support for the fiberglass. The heavier construction of the fiberglass allows a better adhesive bond with the expanded metal grid for superior strength and durability. Compression resistant glass fibers decrease media pad deterioration, extending the life of the filter. Available in a wide range of sizes, HeavyDuty panel filters are used in all types of HVAC systems to protect the coils from dirt. They are also used as prefilters to extend the life of higher efficiency filters.