What card does the telephone world belong to?

Phone World Card belongs to virtual operator calling card.

this card has no roaming, no minimum consumption and no monthly rent, and calls and text messages are cheap. The most famous telephone world cards are the 17 and 171 card segments. The telephone world is the leader of the first batch of mobile communication in China, and the new trend of communication service in virtual operator and China. Cooperative enterprises buy mobile communication services from Unicom, repackage them into their own brands and sell them.