Hand IK Retargeting Node Docs?

I’m looking for info about the Hand IK Retargeting Skeletal Control node.

I know this node wasn’t there before back when I was working on animation in earlier Unreal versions.

I had to do some C++ mods to get my character’s left hand to hold my gun in the right spot and not be a frame behind. I’m hoping this node is useful for solving that but I’m not sure how to use it.