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.

Check the tag inside the shoe: Look for a tag inside the tongue, heel, or arch of the shoe [1]. The model number is usually a 9-digit code located underneath the shoe size. Examine the shoe box: If you still have the box your shoes came in, check the sticker on the side of the box.

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.