Filter, 37mm, 0.4µm, Polycarbonate, Plain White, 1 Back Catalog number: GFPC4537 Manufacturer: SENSIDYNE Availability: In the manufacturer's stock Price on request - + Recommended 202816-1 Filter Housing, Rear GilAir-3/GilAir/5 Price on request 6075-0428-25 Battery Pack Mounting Screw (Sold in pack of 25) Price on request 200156 Luer Taper Adapter, each (See also kit 200156-6) Price on request