The front of this work in anodized aluminum is recessed 1.25 inches. Similar recessed-front single-unit wall pieces were also made in other colors and materials. These shifts in color in material allowed Donald Judd to, “see what happens to the shape and surface.”1 Recessing the front of the work “show[s] the thickness of the sheet metal. . . .  [it] emphasizes the edge more clearly.”2

Judd made works with the same configuration and dimensions as this piece in copper, as well as in red and blue anodized aluminum.

“Don Judd: An Interview with John Coplans,” in John Coplans, Don Judd, exh. cat. (Pasadena, CA: Pasadena Art Museum, 1971), 44.