Code Marked Cards for Naked Eyes

 Code marked cards with unique signs are for you only and no marked cards detector can see the marks. 

With these special marks, you can tell every card with naked eyes and don't need to get any doubtful devices such as the sunglasses or phone scanners. What's more, only you getting the identification method know exactly what the mark is, other people can't know any thing about the marks even he sees it.