What are the holes for on reese weight distribution hitch

Trying to figure out what the small holes are on top.

 

Friction-based sway control. See header image for example: https://shockerhitch.com/product-category/receiver-hitches/sway-control-hitch/

 

The friction bars go into the bottom right?

maybe it’s for safety chains?

 

I thought about the chains, but wouldn't you want the chains connected independent of the hitch pin?

 

Chains go to the pull-vehicle directly to prevent a single-point failure.

 

I think I may have found the answer. This isn't the same hitch. Dual friction anti sway.