Nintendo-licensed to provide dependable, high-performance storage, The SanDisk microSDXC card for the Nintendo Switch system lets you add up to 128GB* of capacity with transfer rates up to 100MB/s(1) so you can keep your favorite titles on a single card and start playing in no time. *1gb=1, 000, 000, 000 bytes. Actual user storage less | (1) 128GB: up to 100MB/s read speed; up to 90MB/s write speed. 64GB: up to 100MB/s read speed; up to 60MB/s write speed. Based on internal testing; performance may be lower depending upon host device interface, usage conditions, and other factors. 1MB = 1, 000, 000 bytes.