DESC: The Ultra 3.5-inch external hard drive enclosure supports Windows XP, 2000, ME and Mac 9.0 and above. Built-in 30 mm cooling fan keeps the drive running at maximum performance while protecting it from excess heat. This easy to use external hard drive enclosure is easy to use – it’s hot swappable, Plug and Play. Lay it down, stand it or stack it! No matter how you use the Ultra portable, stackable enclosure, it will meet and exceed industry standards.