What kind of magic tool do they use?
Marked magic cards are the decks of playing cards processed with invisible ink on the back. The markings are about the detail number and suit of cards. People are not able to see them without any special props. If you want to see them, you should wear the infrared contact lenses or the perspective glasses poker. It is well welcomed by poker players because they can obtain the result directly by using this system.
As to the marking style of contact lenses marked magic decks for poker, it is usually classified into two types. One is a big number with a card suit printed in the middle on the back. The other one is small numbers and suits located at the four corners respectively. Choosing different types of markings relies on various reasons. For example, if you are a poker card magician, the big mark is more suitable for you, which can see the magic decks clearly even in 6 meters away from the table. If you use the contact lenses marked magic decks for poker card games, you can pick whichever you like.