SecureDigital (SD) cards are one of the most common memory cards. They are typically used in electronic devices such as MP3 players and GPS devices in order to store information and make information transfer to a PC easier. However, if you need to check the serial number of an SD card to make sure you have the proper card, you can easily do so.
Remove the card from any electronic device to which it is connected.
Place the card so that the metal end is facing you.
Read the number on the card. Use a magnifying glass if you can't see the number clearly. Note that if multiple numbers are on the bottom, the serial number is the one closest to the metal end, just above the name of the country where the card was made. (For example, the number above "Made in Taiwan" on the card is the serial number.)