Last month I aquired one of these neat salesman samples of a Simplex wire connector. It is marked Simplex/Patent/Made In Holland on the front and Weiss & Biheller Inc./Manufacturers & Importers/584 Broadway/New York City on the back. It is essentialy an oversized version of the small wire nut. 2 inches by 3 inches tall. Here is a picture of the front beside a medium and smaller Simplex wire nuts.