Shortly after taking it out of the box and playing it for an hour or so, I noticed my fingers were hurting, and not in the "I practiced too much - sore finger tips" way. It was higher up on the finger, about half way up the first knuckle, and more toward the inside of the finger. I looked and looked with my naked eyes. I couldn't see anything, but I could definitely feel something, and it didn't feel good. It felt something like a paper cut, but a little different.
I am aware that my eyes are pretty bad these days - I have Tri-focals... I've "graduated" past Bi-focals, lol. So I grabbed my little, direct-from-China-via-eBay, "hand-held digital microscope," which is actually more like a really good digital magnifying glass, with which you can take screen captures. After searching around for just a few seconds, I found several of what you see in the attached picture. That is a picture taken with the "digital microscope." It is a teeny-tiny, invisible to the naked eye, metal splinter. I had several of them. One of them was quite larger than what you see, and stuck in my skin like a sharp little spear. I could clearly see it penetrating down into the skin. I didn't get a capture of that one. To this day, I still have a couple that I couldn't get out, and I can still feel them. It's nothing really painful, but I am aware of them, and the feeling can be annoying at times.
I figure these are tiny shavings from the guitar factory that are left behind after they install and dress the frets (in whatever manner they may dress them). I guess they don't really wipe the fingerboard down before boxing the guitar.
So this is just a cautionary tale, I guess... beware of the tiny metal splinters in your fingers! Wipe down your fingerboard before you play a brand new guitar!
