1. Steel shell: The lower part of the steel shell is finely threaded, which is used to match the spark plug hole of the cylinder head, and the upper part has an external hexagonal nut, which is used to install the spark plug sleeve to tighten or unscrew the spark plug.
2. The metal rod is the center electrode. The lower end of the metal rod is in contact with the upper end of the center electrode through a conductor glass body, and the upper end of the metal rod is equipped with a wiring nut.
3. There is a high alumina ceramic insulator between the steel casing and the center electrode to insulate the center electrode when energized.
4. The bottom part of the steel casing is equipped with curved side electrodes.
5. There is a copper washer in the middle of the outer part of the steel shell.