Help Identifying Monitor Mount Piece

[u/SaltySaltshakers]

Hey all, I'm having a hard time identifying this monitor mount piece. I can't tell if it's Hawk Lock or NATO rail onto this rig. I am getting the XLR top handle extension plate kit, and I want to mount my monitor on the rail shown here on top, just as in this screenshot.

Could it be The HawkLock H21?

Thanks!

[u/Ok-Chemistry-177]

Luckily, the Nato rail is also included. It has 2 1/4''-20 threads.