Thank you Craig Roccanova! What a great gift.
This is a lightweight wood crate 15″ x 11″ x 4.5″ with “Paul E. Wirt Fountain Pen, DURABLE PRACTICAL RELIABLE” burned into it. A flat wood top would have slid into place. The corners have basic dovetail joints. I can only imagine this box containing small cardboard boxes of pens, or even containing hundreds of barrels or sections or caps, ready to be assembled to fill a large order from the Sears catalog.