100% Original SanDisk USB flash drives
Please verify all Flash disks by H2testw on PC
Please test accordng to the port type to test flash disks, if not , speed will be reduced
flash disk is greatly affected by card reader, adapter, USB port etc. Low quality device will 100% slow down card speed.
Based on internal testing; performance may be lower depending on host device, interface, usage conditions and other factors.
About Real Capacity
64GB = approximately 57GB-60GB
128GB = approximately 114GB-120GB
This is calculation difference between manufacturer and your PC, please Google 'Memory card capacity' to get more information.
( actual usable capacity will be less marked capacity (due to the format, operating systems, applications, or other content will occupy part of the capacity)