The security code is the number behind the signature column on the back of the credit card. Just fill it out as required.

The anti-counterfeiting code of the construction bank card is on the back of the card, and the last three digits in the seven digits of the white strip.

The seven digits near the magnetic stripe on the back of CCB Credit Card, the first four digits are the last four digits of the card number, and the last three digits are the security code or CVV code.