The 1-Hole D-Ring Hanger is the only one specially designed for canvas and open back frames. The D-rings are hidden, so the picture never leans off the wall and the hardware isn't exposed. These super strong hangers are also perfect for wall décor accessories such as mirrors. Details: 2 hangers Zinc alloy Each D-ring hanger comes with 1 screw Holds objects weighing up to 25 lb. No studs or anchors needed