I have done some crazy, dangerous, risky things in my life, but the fact is that I am here with you now and that I got out of those crazy things alive. sometimes to help others in need, sometimes to do something for myself, I ran into various situations and "put my head in a bag". almost like in the song of one of our singer-songwriters:" When I get beaten I don't cry I was beaten and I beat because then, then I was young".
As for this nut in the picture, I'd say it's on your weapon, probably on the optic and fine adjustment mounting rail...
Hmm, good guess indeed...let me see if anyone else gets more specific, then I'll stand having out billions of bonus points.