Yellow translucent mini post originally used on Jersey Jack Pinball's The Hobbit pinball machines.
In regards to functionality, but not color, this plastic post is also a suitable replacement for all the part numbers listed below.
Williams/Bally reference #03-8044-9, 03-8044-13 & 03-8044-12.
Stern/Sega/Data East reference #550-5052-01 & 550-5052-02.
American Pinball reference #PST0006-00.
Chicago Gaming Company reference #PIN-03-80449 & PIN-03-804413.