How does the Agricultural Bank inquire about the balance? This is a passbook, not a card.

The settlement passbook can only be used for personal online banking in the province, and its use is restricted. Bank transfer in different places is supported, but inter-bank transfer is not supported. You can bring your valid ID card, current settlement passbook and payment password to any branch of Agricultural Bank of China in the province where the passbook is opened to sign up for personal online banking. This business is not allowed to be handled by agency or temporary id card. Online Banking: log in to personal online banking, click "Account-Bank Account", and then click "Show Balance" to display the available RMB balance of this account.