Briggs & Stratton Spark Plug (RJ19LM). If the engine does not start or runs poorly then the spark plug may be defective and will need replacement.
Genuine Briggs & Stratton 495606 Carburetor Rebuild Kit. If the engine is running poorly then the carburetor may be restricted and need to be cleaned and some of the internal seals and diaphragm replaced.
Small engine carburetor assembly. If the engine runs rough, then the carburetor may be restricted and unable to supply enough fuel and air mixture to the engine.