Sierra International 18-4220 Marine Thrust Washer for Mercury/Mariner Outboard Motors Sierra Thermostat Meets or exceeds the original equipment quality Sierra part number: 18-3552 Interchangeable with the following: GLM 13050, Crusader 96358, Mallory 9-4300, Mercruiser 76270, 76270T Fit specific, check part numbers to ensure proper fit