One of many illustrations created by Syd Mead for a promotional brochure distributed by US Steel in the late 1960s and early 70s.

US Steel would send the brochure for free to anyone who asked and nearly everyone in the art department at ILM, which produced the visual effects for Star Wars, had one. According to Joe Johnston, who was the visual effects art director on the film, this particular illustration served as the direct inspiration for the AT-AT vehicles in The Empire Strikes Back.