The mounting holes are shaped as a keyhole, so the parts slide in and are tightened.
This allows parts to be installed and removed easily.
Installing a AR 15 Free Float Rail is not complicated. It is relatively straightforward and not a lot of special tools are needed.
It was pretty easy, even easier than building a stripped lower.
You will need a barrel wrench, an action block to hold the receiver, a vise, and a torque wrench.