Spark plug with automatically adjustable gap

Spark plug with center electrode having high heat...

Spark plug with center electrode having variable diameter portio

Spark plug with copper cored ground electrode and a process of w

Spark plug with electrode including precious metal

Spark plug with electrodes having noble metal inserts

Spark plug with engine cylinder pressure sensor

Spark plug with enlarged center electrode and gap

Spark plug with fine wire ground electrode

Spark plug with ground electrode having diverging prongs

Spark plug with ground electrode having mechanically locked...

Spark plug with heat conducting sleeve for center electrode

Spark plug with igniting portion chip composition

Spark plug with improved noble metal chip

Spark plug with inclined electrode spark surfaces

Spark plug with increased durability and carbon fouling...

Spark plug with increased durability and carbon fouling...

Spark plug with Ir-alloy chip

Spark plug with iridium-based alloy chip

Spark plug with iridium-rhodium alloy discharge portion