Spark plug having noble metal tip

Spark plug having noble metal tip

Spark plug having resistance against smoldering, long...

Spark plug having ring shaped auxiliary electrode with thickened

Spark plug having spark portion provided with a base...

Spark plug having specific configuration of center electrode...

Spark plug having specified spark gap dimensional relationships

Spark plug having tapered ground electrode

Spark plug having titanium diboride electrodes

Spark plug having vanadium oxide islands on central insulator

Spark plug having Y-shaped or V-shaped electrodes

Spark plug in use for an internal combustion engine

Spark plug in use for an internal combustion engine

Spark plug including a ground electrode, a center electrode, and

Spark plug including electrode with protruding portion for holdi

Spark plug including ground elcetrode carrier casing

Spark plug incorporating a folded packing situated on an...

Spark plug insulator for use in internal combustion engine

Spark plug insulator structure

Spark plug internal combustion engine