Blue Crown A2 Model Engine Spark Plug.

.940 overall length, 1/4-32 thread, 3/8 hex.

 

See Our Miniature Spark Plug Collection at: www.flickr.com/photos/15794235@N06/albums/72157651839098937

 

See Our Miniature Engine Collection at: www.flickr.com/photos/15794235@N06/albums/72157602933346098

 

Visit Our Photo Albums at: www.flickr.com/photos/15794235@N06/sets

 

Courtesy of Paul and Paula Knapp

Miniature Engineering Museum

www.engine-museum.com

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