Sierra International 18-3555 160 Degree Marine Thermostat for Mercruiser Stern Drive Sierra Thermostat Temperature rating: 160 Sierra part number: 18-3555 Interchangeable with the following: GLM 13040, Mallory 9-43001, 9-43016, Mercury 99155A1, 99155T2 Fit specific, check part numbers to ensure proper fit