Luminous ink is very useful device for tricky, including the special cheating case, magic shows or poker game cheating. In order to see luminous ink mark, you must have the " luminous contact lenses ". What is the luminous contact lenses? It's a pair of special contact lenses that can help you to see the invisible markings. The contact lenses are the most effective and discreet way to read the invisible markings. The contact lenses are made of the same material regular contact lenses are made out of. Luminous ink for marking cards works well with the marked cards contact lenses as a kit. That means one pair of luminous contact lenses is necessary to see the invisible ink marks for cheating without others' notice.