Our suncatchers are intended to be hung in any window that gets some sun. We recommend hanging them from a cup hook that is screwed into the window frame or an “s” hook that hangs from a curtain rod. A suction cup at least 1.5” in diameter may work, but use at your own risk. Make sure that the surface is clean & dry before attaching. We DO NOT advise using suction cups for the “Grand” size suncatchers or larger.