You can display lightweight signs and products from metal surfaces with these magnetic hooks. Magnets are easily placed and removed. Attaches well to most ferrous metal surfaces. Warning: Holding capacity is the approximate maximum pull rating under ideal conditions. Always test suitability on a per application basis. For best results, use on an indoor, bare (unfinished) metal surface that is smooth and clean. Metal conditions will affect holding power. Magnets should not be used near electronic equipment.