In 1963, Dan Flavin adopted fluorescent light as the primary medium for his art, employing standardized bulbs and confining himself to the limited palette and dimensions that were commercially available. Within this restricted vocabulary, however, he discovered a remarkable range of possibilities as he tapped into the optical dynamics embedded in these common and everyday materials. This untitled example, created a year before Flavin’s death, introduces an ultra-violet element that vividly sets off the green and red tubes, as color is cast upon a mural surface without boundaries, diffusing imperceptibly, and responding to the site-specific conditions of each installation.