1, starting from the left hook tip and ending with the letter "u" of "Britain", connects a straight line, and the extension line of the straight line just passes through the decimal point of "7.5" under "Britain" and coincides with the central axis of the third article number.

2. If the size under "UK" has no decimal point and is a number, the extension line passes through the central axis of the number.

3. The factory code is in the upper right corner of the double horizontal line, and the letters correspond to the numerical positions, for example, "27.5" corresponds to "cm".

There are two types of bar codes: thick line and thin line. The third thick line will not appear on the genuine product.

5. The number column corresponding to 5.UPC barcode is still 14, and the first two digits are 0. After deleting the first two digits, the remaining 12 digits should correspond to the UPC serial number on the shoe box.