The MP7906 Magnetic Pickup (3/4" x 3" long) has a total length of 3 inches, threaded length of 3 inches, and thread size of 3/4-16 UNF. It replaces 20-01-0081. The leadwire hookup measures 12 inches (305 mm).
WE OFFER AN ALTERNATIVE PART with same specs $80.00

Type Part number MUI-MP7906 in search bar.

Magnetic Pickups supply RPM data to a tachometer when mounted at the flywheel ring-gear of an engine.