This is a brand new shutdown solenoid for Onan p/n 307-2546, Woodward p/n 1502-12D6U2B2S1A.
The plunger is internally threaded with 1/4x28 threads.
12 Volt
*This is an internally switched solenoid, which requires the plunger to be fully seated when the solenoid is energized, to prevent coil burnout. *