USB2.0 Lightning to TF Card Reader Please upgrade iPhone system to IOS13 for usingSupport iPhone6 / 6s / SE / 7 / 7s / 8/8 Plus / X / XR / Max / 11.etc ... Feature: Plug and play (no software needed) Micro SD + TF format,High-speed read and write 8GB,16GB,32GB,64GB,128GB,256GB Storage Size Applies to Cell Phones, Cameras, MP3/MP4 Player and More device Can be Used as Micro SD or SD Card Operating Temperature - 13F to 185F(- 25C to 85C) Storage Temperature - 40F to 185F (- 40C to 85C) About capacity: 16GB=approximately 14GB-15GB 32GB=approximately 28GB-30GB 64GB=approximately 58GB-60GB 128GB=approximately 116GB-120GB 256GB=approximately 228GB-236GB This is calculation difference between manufacturer and our PC, please Google 'Memory card capacity' to get more information 16GB/32GB=Class 10 speed U1 64GB/128GB/256GB=Class 10 speed U3 Original high quality flash memory Warm Tips: Please don't use cheap card reader to test memory card, speed of memory card will be reduced by low quality card reader The most reliable software to verify memory card is H2testw **memory card speed is greatly affected by card reader, adapter, USB port etc. Low quality device will 100% slow down card speed. **Up to 40MB/s read speed; write speed lower. Based on internal testing; performance may be lower depending on host device, interface, usage conditions and other factors. 1MB=1,000,000 bytes.