This is a shared credit line. ETC credit card is also a kind of credit card, which shares the same credit limit with other CCB credit cards under your name. If you have a secondary card in your name, then the secondary card will also occupy your quota. If you use this card, the available amount of another card will be reduced accordingly. However, it should be noted that repayment cannot be universal, and repayment should be made separately according to the card number.