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I bought a 'Box-O-tools' a couple of weeks ago and found this.
It seems to be some sort of clutch drive adapter.
The inside diameter is 3/8" and there is a 1/4" socket inside, that might or might not be magnetic.
When you retract the outside barrel the ball bearings loosen up.
What I think is the ‘drive shaft’ is 7/32".
Any thoughts from this esteemed group would be welcome.