Freecom Mobile Drive Mg 1.5TB USB 3.0 Portable External Hard Drive with Magnesium Enclosure for MacBook 97713 (Silver) Ultra thin mobile hard drive in stylish design, complements the design of your MacBook Magnesium enclosure: ultra lightweight, high quality, solid and environment- friendly material Connects to the USB port of your MacBook Mac HFS+ formatted, immediately ready to be used on your MacBook and 100% Time Machine compatible No cooling fan, ensures quiet operation High quality and sleek design Green - Magnesium is an earthly matter. It is produced from sea water, brines and magnesium-bearing minerals, which offer unlimited reserves