Sierra's 18-3377 Water Pump Kit without Housing is designed for use with Johnson/Evinrude 10 HP (1949-1957), 15/18 HP (1953-1965), 20 HP (1966-1973), and 25 HP (1969-1978) outboard engines. The kit contains: (1) Sierra 18-3002 Impeller, (1) Sierra 18-3103 Impeller Plate, (1) Sierra 18-3326 Impeller Key, and (1) Sierra 18-3329 Grommet. It is interchangeable with Johnson/Evinrude Outboard 0379773 and 0382468. Each Sierra product meets or exceeds the original equipment part it replaces. Fit specific, check part numbers to ensure proper fit.