Sierra 18-2785 Lower Unit Seal Kit Sierra Lower Unit Seal Kit Contains two oil seals (18-0296), two oil seals (18-0554), three drain fill washers (18-4698) Sierra part number: 18-2785 Interchangeable with the following: Mercury 27-41899M, 27-84828M, Yamaha 689-W0001-C1-00, 689-W0001-21-00 Fit specific, check part numbers to ensure proper fit