Ok in order to get some intrest to sell your mod you realy need to know or you need to tell people excactly what the thread inside the mod is,ie 1/2unf,1/2unef,m14x1,5/8unf,5/8unef and theres a load more,if the guns thread can be checked by a gunsmith or gunshop or you know what the thread on the gun is that the mod fits,and it isnt a mod that you have bought thread unknown then the rifle thread will tell you but at the end of the day buddy mod thread needs to be known cheers paul.