It's a bigger button, what else is there? - Lockstep Arms Oversized AR Magazine Release

It's what you'd expect. The plate brings the mag release a little closer to the trigger so it's easier to manipulate with smaller hands without adjusting grip.

It feels a little loose on my receiver, but that may be a consequence of applying pressure that is not inline with the spring/hole.

For the price point, I'm satisfied. It does what I needed it to do.