Construction set:American Plastic Bricks Set No. 725

Elgo Plastics first offered its American Plastic Bricks in the 1940s. A division of the Halsam toy company, also located in Chicago, Elgo used the injection molding process to mass produce its uniform, interlocking building bricks. Halsam's American Plastic Bricks sets were taken over by Playskool, which then became a part of Milton Bradley in 1968, and thus part of Hasbro, Inc., when Hasbro acquired the game company in 1984.