Sierra's 18-3569 Thermostat Kit fits various Mercury/Mariner 70-125 HP 2 cycle outboards (1987 and newer). The kit includes (1) 18-0182 Thermostat Gasket, (1) 18-0339 Thermostat Cover Gasket, and (1) 18-3549 Thermostat. It is interchangeable with GLM 13124, Mallory 9-43155, and Mercury Marine 803061T1. Each Sierra product meets or exceeds the original equipment part it replaces.