I have the same problem with my Charles Daly 28 gauge. The threads look just like Mobil choke thread, BUT THEY ARE NOT THE SAME. I bought a Briley Turkey choke Mobil ,nope.
The best way to describe it is that the threads don't have a peak, instead it's flat threads. It's supposed to be Mobil.
Have a good one, May God bless y'all
Bo
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