Plain and simple, this portable hard drive is an easy way to add storage to your PC or Macintosh notebook computer. Is it reliable…of course, it's from Western Digital. Portable drives that are easy to use, light and easy to carry, and require no power adapter--they are powered directly through the USB cable. Weighing in at only a few ounces, these tiny drives fit easily into pocket or purse. Ideal for carrying large files between work and home or on the road.