The wall mounted stay roller is an optional bottom guide for sliding doors. It is a great solution for situtations where the floor cannot be drilled to accomodated other guide options (such as the t-guide, or c-guide). The stay roller mounts to the wall and makes a u-shape, curling beneath the door and out to the other side. Minimum door thickness is 1-1/2", maximum door thickness is 2-3/4". Black powdercoated steel with a black nylon wheel (screws included).