What is the standard for micro-credit international telephone charges?

What is the standard for micro-credit telephone charges

Currently in the Google Play Recharge page can see the micro-letter phone charges, from abroad to China's main call telephone charges for every 0.99 U.S. dollars 110 minutes, the equivalent of RMB 6 cents per minute, this for transnational telephone, is undoubtedly quite cheap

Note: Small series don't think this micro-letter phone directly use QQ or easy to letter is not entirely free, especially domestic telephone use letter is free of charge, the use of QQ voice is free, why pay the phone, of course, the network phone must have a delay problem.