Be aware that there is a proliferation of fake and counterfeit memory cards sold online, particularly on eBay. If the price is too good to be true, it probably is.
Counterfeit cards may work but the write speed is often much slower than a genuine card. Though sellers claim otherwise, counterfeit cards usually do not have a valid warranty.
For example, secure digital memory cards made by Sandisk are frequently counterfeited. Genuine Sandisk memory cards have a shallow notch at the bottom edge of the card. The edge of a fake is completely smooth.
Packaging of a genuine Sandisk card says “Limited Lifetime Warranty,” not just “Lifetime Warranty.” Sandisk products have serial numbers on the back of the card. Fake cards usually have no serial number.
Sometimes unscrupulous sellers use images downloaded from the SanDisk website. However, they are not representative of the actual item you’ll receive.
Buy from a reputable vendor
Seriously consider the risks before buying an all-important memory card online from an unknown source. Prices of memory cards have come down and are often on sale. If you want to buy online, pay a little more and purchase from a reputable vendor such as Amazon [Visit our Amazon Store for camera products and user reviews]