Which model(s), product numbers appreciated, are "standard" military issue?
If they are different I'd like to know:
Which is used on M4s?
Which is used on M16A2s and A4s in both the Army and Marine Corp?
Also, what is the standard mount(s) if different between the branches?
Finally, which BUIS work with the above?
Again, if they're the same for all I apologize for my lack of knowledge and thank anyone who can provide some info.
I did try the FAQ tacked at the top but it doesn't seem to work.
Thank you,
Scott