What POS machines fear most is code skipping. The question of whether to skip code with pay has been going on for a long time, but no one can tell you why.

So to judge whether a POS machine is good or not, you have to find out for yourself.

First, install a China UnionPay Express software on the mobile phone, then bind the swiped credit card with the attached payment, find out a transaction record, and look at the name and number of the merchant who swiped the card.

Then take the merchant information to the official WeChat account of a letter to see if the merchant information of the credit card is true.

Check the name of the merchant first to see if it is true.

Finally, check the merchant number information to see if the merchant is the kind with a rate of 0.6, and whether there are credit card points and the like.