This part is the replacement spark plug for your engine. It measures approximately 2.5 inches by 1 inch. The spark plug creates the spark that ignites fuel in your engine during the combustion process. Over time, spark plugs can become worn and can go bad, which will prevent the engine from firing. You can test your spark plug for continuity with a multimeter, and inspect it for corrosion if you suspect the spark plug has gone bad. This is an OEM part sourced directly from the manufacturer and it is sold individually.