I purchased a SD card from the seller Digital Media Source off Amazon.com. According to their refund policy, within 21 days of the order being placed I may contact Digital Media Source to request a refund. I did not receive any response from them at all after I contacted them through Amazon. Even if they decided they wouldn't give me a refund, I would have appreciated at least an explanation. So beware if you get anything from them, don't expect any response after you pay.