The IBM Portable Personal Computer 5155 model 68 was an early portable computer developed by IBM after the success of Compaq's suitcase-size portable machine. It was released in February, 1984, and was eventually replaced by the IBM Convertible.

The Portable was basically a PC/XT motherboard, transplanted into a Compaq-style luggable case. The system featured 256 kilobytes of memory (expandable to 512 kB on the motherboard), an added CGA card connected to an internal monochrome amber composite monitor, and one or two half-height 5¼" 360 kB floppy disk drives.

More Info: en.wikipedia.org