Professional X series SDXC (Secure Digital Extended Capacity) is the latest high speed flash memory card from PNY. These cards are rated Class 10 and feature a new Ultra High Speed (UHS-1) data bus for incredible transfer rates with speeds of up to 50MB/s seq. read and 35MB/s seq. write. These cards are compatible with SDXC host devices ranging from the latest hi-megapixel cameras and HD camcorders to hi-end DSLRs and laptops.