Sorry, there. I was referencing Figure 87, the 1/4" Drive Handle and Rotating-Grip Extension.
There is really more to it than a quick glance will tell. Armstrong was big on putting knurled rotating grips on their stuff, but this one has two pins on the shank that lock the rotating grip. So, you can turn the tool if it is locked--or use it as an extension if it is unlocked.
The top end is recessed to take a driver of some sort. Actually, mine is the 9/32" version.
Note that Williams hade a very similar tool and put it in lots of electrical tool sets.
BTW, I wish the best for Papaw just like you guys do.