WWII US dexterity game - Trap a Sap

Handheld dexterity puzzle with blue metal sides, glass top and a cardboard lithograph background featuring US soldiers and tanks shooting down planes. There is a small square of cardboard at the centre top of the puzzle and three plastic capsules, weighted at one end with a small metal ball bearing.
The aim of the game is to juggle the capsules into the cardboard square through a small hole at the base.
The reverse of the game is bright yellow card.

As with most of these vintage dexterity puzzles, they have become harder to complete due to the warping of the cardboard base.

One of a series of 6 handheld dexterity puzzles in the collection produced in the United States during WWII.