Model Compatibility: Fits M651 E200 GLK250 vehicles as a direct replacement for the engine coolant thermostat. Part Number Match: Replaces part numbers 6512002700 and 6512000915 specified in the application. Functional Equivalence: Restores engine coolant temperature regulation function without modification to system design or. Installation Requirement: Designed for installation in the same location and orientation as the thermostat in M651 E200 GLK250 models. Application Specificity: Intended for use as an engine coolant thermostat in the M651 E200 GLK250 vehicle configuration.