Although there is no integral, I still answer you,,, this,, there is no such thing, especially on the back of the card. For your safety, is there 7 digits on the back of the card? Prove that the card is valid, which can change your credit. . . Once your credit card reader has a recording function, you will copy your card if you provide it. . . Specifically, you can type the nuclear manual and ask if you have this thing. If you don't have this thing, it is fake.