This is a combination of numbers and letters located at the bottom of the shoe label. According to Adidas regulations, each pair of shoes will have a different component code. Moreover, if they are genuine shoes, the component code on the left shoe and the right shoe will be different.

Adidas sizing is generally true to size. The label themselves advise that for a more loose feel, you should go up a size or, for a more snug fit, try a size smaller. These are, after all, relaxed sports-oriented pieces that need to fit your particular lifestyle.