14mm male thread for use with OTC comp compression testers (or other compression testers with a 14mm male thread) to access hard-to-reach spark plug holes.

• Works on 2008 and newer Ford 4.6, 5.4 and 6.8L 3-valve engines with 12mm spark plugs
• 7" long with 12mm male thread, 14mm female thread
• Easy-to-turn feature makes starting thread fast