Peek a boo scan?

I was waiting for my doctor when I read a sign in the room about having a “peek a boo” scan to find out your baby’s sex at just 14 weeks, I believe.

My question is, is that a 3D ultrasound? And will insurance cover that? I want to be covered and not get caught up in the excitement and end up with a big fat bill later on. I’ll end up calling my insurance company but wanted to see if anyone on here knew about them?