Replica 18mm Spark Plug Set

These spark plugs are for the antique motorcycle enthusiast who enjoy riding. Spark plugs are air cooled with a heat range #3. Includes the brass top nuts which are used with earlier style terminals or hood style and sealing gaskets.
Exact duplicates of the "globe" 18mm spark plugs of 1937. Harley Davidson fought with Champion Spark Plug over the construction of this air cooled plug, so Harley contracted with Globe for this year. Terminal nut is removable. Plug set requires a round feeler gauge. "Globe" style plug has no markings except heat range #3. Spark plugs have a 1-1/8" hex shape and 18mm thread. Brass terminal nuts and seal washers included.