Sierra 18-2648 Upper Unit Seal Kit Sierra replacement upper unit seal kit for Mercruiser Stern Drives. Sierra replacement engine parts are manufactured to meet or exceed OEM requirements. For 1 Units Including Alpha Also fits 888 stern drive sn 3106717 Up Kit Includes 1 18-0894 Water pocket cover gasket 1 18-2003 Oil seal 1 18-2049 Oil seal 1 18-2056 Oil seal 1 18-2944 Seal ring 2 18-2945 Drain screw gasket 1 18-3110 Water pump housing bushing 2 18-7153 O-ring 1 18-7161 O-ring 1 18-7169 O-ring