I think that is a lug nut socket. Sears used to sell a "Lug Nut Magazine" that held 5 lug nuts in either 3/4" or 13/16" size. It was meant to be used with an electric impact or "hand wrench" that was a 4-way wrench with 1/2" drive on two short opposite ends and plastic knobs on two longer opposite ends.
The socket had a rubber band looking thing on the open end, probably to prevent wheel damage with the electric impact. The holes probably helped hold it on.
It's in my 1959ish Craftsman Hand Tools catalog page 11, lower right. Part number is 9 M 4278 and state the size, 3/4 or 13/16. I don't see it in my 1966 Craftsman catalog.