Part Number: 9.803-535.0 Cross Reference Part Number(s): 091526, 2-011571, 817312, 98035350 This 9.803-535.0 Black DIESEL Fuel Cap with gauge is used on portable, diesel fired hot water pressure washers. 14 inches in length, this fuel gauge is compatible with many diesel supply tanks; it may fit on other brands of supply tanks, but we cannot guarantee the accuracy of the fuel gauge, due to depth of tank. The BLACK cap indicates diesel fuel, while a RED cap indicates gasoline.