The model number (or SKU) of a shoe can be found on a label located on the inside of the shoe tongue. RN stands for registered identification number. It is a number assigned by the FTC to US businesses that manufacture, import, distribute or sell products covered by the textile, wool and fur Acts.

The model number of your shoes is typically located under the size and above the barcode on the tag.

Examine the SKU number on the box and the labels inside of the shoes. Every pair of authentic Nike shoes comes with an SKU number that is identical to the SKU number on their box. If the numbers are missing or do not match, they are likely fakes. Check the tongue label.