Stainless Steel Water Filter System Housing 20 inch x 4.5 inch standard 1 inch BSP inlet and outlet ports. This quality full stainless steel housing will take all 20″ x 4.5″ water filter cartridges. Heavy duty housing ideal for inside or outside applications. Made from 304 stainless steel, NSF certified, Australian Watermark Complied. Includes sturdy stainless steel bracket and opening tool suitable for temperatures up to 99°C. Free delivery Australia Wide.