IPR Nut Size ?

[nadekeys]

Does anyone know the actual size of the stamped IPR nut? I want to replace the one that i have currently with an actual nut as the stamped one keeps working its way loose and falling into the valley. Is it a 1/2" x 20 (fine threaded) or is it some metric size? Thanks for your input.

[nadekeys]

For everyone's future reference, the nut on the back of the IPR is indeed a 1/2" x 20 fine threaded nut. I put it one on last night with a few drops of loc-tite, hopefully that does the trick and I won't find it lying in the valley anymore.