Crucial 64 GB m4. Solid-state drive capacity: 64 GB, Size: 63.5 mm (2.5 "), Solid-state drive interfaces: Serial ATA. Read speed: 415 MB/s, Write speed: 95 MB/s, Random write (4KB): 20000 IOPS. Operating voltage: 5 V. Mean time between failures (MTBF): 1200000 h. Operating temperature range (T-T): 0 - 70 °C, Storage temperature range (T-T): -40 - 85 °C, Operating shock: 1500 G