Sierra's 18-3500 Thermostat features a 140° temperature rating. It is designed for use with Johnson/Evinrude 3 Cylinder (1992 & Up) and 90° Looper (1990-1992) applications. Includes one thermostat per package. It is interchangeable with GLM 13170 and Johnson/Evinrude Outboard 394409 and 434137. Each Sierra product meets or exceeds the original equipment part it replaces.