ChampionIridiumPlugs.com is part of the SparkPlugs.com family, an authorized full line Champion dealer. We are not Champion Spark Plugs USA. To contact them, click here.
The top of a spark plug contains a terminal, which serves as a connector to the ignition system.
There are 2 connection types available. Some applications utilize a boot that connects directly to the threaded terminal stud. However, most vehicles use a boot with a larger connector inside, made to snap onto a terminal nut.
Spark plugs used for both terminal nut and threaded stud connection types may come with a removable terminal nut. In this case the plug is manufactured with a threaded terminal stud, then a screw-on terminal nut is added to the plug or package. This allows the plug to be used with either connection type.
Plugs with a solid terminal nut can only be used with the larger, snap-on connector type. The terminal is part of the plugs design and cannot be removed. Most automobiles utilize this type of connection system.
In cases of high vibration, a removable terminal nut may become loose and create an insecure electrical connection. Therefore if a terminal nut is used on marine, ATV, or similar applications, a plug featuring a solid terminal is preferable, if available.
The use of terminal studs as a connection type is most common in motorcycle and power sports applications.