1/2-20 unf 3a thd size
No other part numbers with same form, fit, and function found.
A shaft having two or more different diameters (greater than 0.031 inches (0.79 millimeter)) along its length. It must have one or more of the following conditions: a specified surface finish designation in the range 1 to 125 microinches (0.025 to 3.2 micrometers) arithmetical average (aa), machined peripheral flat(s), circular groove(s), keyway(s), splines, threads, or holes. The ends and/or shoulders may be machined to accommodate bearings, couplings, and the like. It is not designed for use in aligning by fitting into corresponding holes of another item. For items used to support rotating members see axle(1), shouldered. For items not having any of the above conditions see pin, shoulder, headless. Excludes shaft(1), straight; and axle(1), straight.
Classification: Transmission shafts and cranks, except camshafts and crankshafts
NSN 5930-01-537-1167
NSN 6105-01-145-8109
NSN 2925-01-422-1542
NSN 5999-00-932-0221
NSN 6130-01-569-2159
NSN 6645-01-044-6376
NSN 4140-01-370-4075
NSN 6105-00-058-8915
NSN 5895-01-128-3218
NSN 4140-01-627-2540
NSN 5960-01-179-9350
NSN 5975-01-130-4268