Antique letterpress printing
Despite their (perhaps well placed) skepticism you confidently remove their 'invisible card' from the deck and slide it between two face up jokers
And it's not just a ring trick
This book helps greatly with that in a very entertaining way
Trick can be performed at the same time for 20+ spectators -- they all see the video
Infra Red Box | Werry Münzdose Antique letterpress printingWerry's INFRA RED BOX A white disc is signed on both sides, one by you and the other by a spectator. It is then placed in a transparent box. Now the spectator chooses a card. When the disc is taken back out of the box, the signature and the card value appear on it, as if by magic! Of course, in addition to card values, ESP signs, predictions, geometric symbols, etc. can also appear. The box can also be used as a transparent Okito container.