Rugged, Heat Sealed Construction. Flanders Precisionaire Ring Panel and cube filters are made by heat sealing layers of synthetic media together over an interior, corrosion resistant steel support frame. An over cut of media outside the seal forms a built in gasket (selvage) between the wire support frame and holding frame, which secures the filter and prevents air bypass. This special feature allows these filters to be installed without the use of retainer fasteners.
