Magnetic signs Takkis. Self-adhesive, permanently magnetized discs. For magnetically attaching paper and cardboard to ferrous surfaces such as whiteboards, flipcharts, and display cases. Versatile use: Simply remove a Takki, peel off the protective film, and stick it on the back of paper or cardboard. Everything will then hold invisibly on the surface, with no distracting magnet in the line of sight.