They hold through glass! simply place a magnet on each side of the glass, then hang the sign or decoration. Can be used with single pane windows or as single hooks on metal doors. If used on a metal surface, each hook will hold up to 35 lb protective coating helps prevent scratching. Recommended use for single-pane windows only.
Each of these metal hooks offers users unique holding functions and non-scratch liners. Neodymium magnets provide industrial-strength holding power. Ideal for holding and storing tools, cables, signs and other heavy items.