Visa credit cards are divided into single-currency cards and dual-currency cards. In China, most of them are single-currency cards owned by UnionPay. Customers who go abroad will use dual-currency cards with double logos of visa and UnionPay. On pos machines and whether to swipe visa credit cards, domestic pos machines only support UnionPay logo credit cards, but not++cards, which require a specific cross-border card swiping machine to use: 1)visa cards can swipe pos machines; 2) places that support visa card swiping; 3) commission rate

So much for the introduction of pos machines with US dollars.