Compression Tester 12mm Spark Plug Adapter for Ford 4.6L 5.4L 6.8L 3-Valve
Connect Tester: Connect the compression tester to the adapter. Attach Adapter: Screw the adapter onto the compression tester's hose. 7”Long 12mm Male, 14mm Female threaded adapter connects to OTCand other compression testers with14mm thread.