sorry to say but your wrong about that.
When most people talk about mil spec v civi buffer tubes they are not talking about the threads, but the specs on the body.
But there is allso mil spec v civi AKA made in china thread pattens.
The thread is different and most times both will fit with no problem, but when you get somthing that is machine rather then taped, Like a stock adaptor on the endine buffer.The mil spec or civi can be to tight or too loose and bind.
So the "combo thread) is mil spec pitch with flater edge so both mil spec and civi will fit.
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