Italy Modiano cristallo marked cards can made with our invisible ink on the back of the cards,when you wear our perspective glasses or UV contact lenses
you could see the number and suits of the marked cards clearly.
We marked this cards with invisible ink, so the player wear special contact lenses can see the invisible marking.
There is not any other better than this device ,you know all the cards on the table easily and quickly.
Other players can't see differences between normal cards and marked cards,only the player who wear the special uv contact lenses or perspective glasses.