Excellent value for money, to see over time, some having had some problems ... For the lifetime warranty is only valid if the registration card on the Transcend website, max 30d after purchase. For those who have had registration problems: the serial is not composed of 10 digits as instructed on the site; but one letter and five numbers (eg B66666) present on the front of the micro-sd (just below the marking "64GB"). It may be checked because the recorded serial match the reference "TS64GUSDU1E" which is that of the 64GB card.