large linear potentiometer part no. c-10B-2738 vintage

Subject: large linear potentiometer part no. c-10B-2738 vintage

This item is rather unusual. Appears to be around 1940's - 1950's era Linear Potentiometer. It is in LIKE NEW condition in it's original box.
Written in pencil on one side of the box is 10,000 ohm and the word linear.
Military contract part, label reads as follows:
Control, Large (Potentiometer)

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