The With Flange Flame Retardant Air Filter Cartridge is made of American high-quality high-efficiency flame-retardant wood pulp fiber filter material, combined with advanced folding technology, so that the filter cartridge has the characteristics of non-combustion, large filtration area, small pore size, large air permeability, low resistance and high efficiency; The end caps and the inner and outer protective nets are made of high-quality galvanized sheet, which has good anti-corrosion and anti-rust performance.