Viskon-Aire 865-006 Series 55 Green 20" x 20" Intake Filter Panel (Internal Wire) Utilizes Viskon-Aire's unique "Never Dry" PBT-32 tackifier and includes filter-change indicator Competitors call their products "Series 55", but they lack Viskon-Aire's quality, durability and performance Self-sealing gasket and internal wire frame eliminates air by-pass and media flutter to keep dirt out of your spray booth