On the tongue in the original pairs from Nike There is the brand's logo. On the inside of the tongue on the tag should be product information, including size and country of manufacture. There is also a 9-digit serial number, which should correspond to the code on the box.

Nike tags can be used to identify the exact year and season the garment was released. A serial code normally placed on a smaller label amongst the wash tags is the first point of call. The first four characters of the 6-12 character Nike serial code designates the year and season.