Use the main card. Etc recharge is with the main card. ETC card configuration, car cards are consistent, the main card is pre-borrowed, transferred and recharged, and the credit line is allocated to the secondary card. The card comes with the car and is kept by the car companies. Just deposit the money directly into the bank card bound to ETC. After the vehicle passes through this card channel, the toll is automatically deducted from the bound bank card through the bank, and a certain amount must be reserved in the bank card at ordinary times.