Like Meccano, it consists of collections of small metal beams with regular holes for nuts, bolts, screws, and mechanical parts such as pulleys, gears, and small electric motors. Erector beams have flanges, which make them more sturdy than those of Meccano.

The Erector Set was invented by A.C. Gilbert in 1911, and was manufactured by the A. C. Gilbert Company at the Erector Square factory in New Haven, Connecticut, from 1913 until its bankruptcy in 1967. It is manufactured today by Meccano S.N. of France, part of the Nikko Group of Japan. In the U.S., since Jan. 2006 it is distributed by Nikko America.

The Erector Set is said to have been the subject of the first national advertising campaign in America for a toy. Its great success made it part of American folk culture, although its popularity has faded in recent decades in the face of competition from molded plastic construction toys, electronics, and other more \"modern\" toys.

Scores, perhaps hundreds, of different Erector Set kits have been made over the decades, most famously the \"No. 12 1/2\" deluxe kit that came with blueprints for the \"Mysterious Walking Giant\" robot.

An extensive collection of Erector sets, model trains, chemistry sets, radioactivity experimentation kits, microscopes, and other A. C. Gilbert Company scientific and educational children's toys is housed in the Eli Whitney Museum, in Hamden, Connecticut.