1. NFC TAG
There is an NFC tag in the artwork that leads to "www.graphixguy.art/Collectors"
If the link does not lead there, DO NOT open it.
It may be a counterfeit print.
2. HAND WRITTEN NOTE
On the back of the artwork there is a handwritten note showing the number of the artwork that has been sold. e.g "GraphixGuy 01 - No. 44"