Nice find.
One of the neat things about that design, as you no doubt know, is that it permits the ratchet head to be thinner, because there's no need for a reversing mechanism: you just push out the male socket receiver and (in your case, with the flange on one end of the receiver) push it in from the other side. I've got a Craftsman ratchet of that design, waiting for the day that I need that extra 1/4" or so of clearance.