Speed 256GB up to 280MB/s read, up to 180MB/s write 128GB up to 280MB/s read, up to 100MB/s write Operating Temperature: -25°C to 85°C (-13°F to 185°F) Storage Temperature: -40°C to 85°C (-40°F to 185°F) Dimension (L x W x H): 11 mm x 15 mm x 1 mm / 0.43 x 0.59 x 0.04