The PowerBook Duo was a line of small subnotebooks manufactured and sold by Apple Computer from 1992 until 1997 as a more compact companion to the PowerBook line. Improving upon the PowerBook 100's portability (its immediate predecessor and Apple's third smallest laptop), the Duo came in seven different models. They were the Duo 210, 230, 250, 270c, 280, 280c, and 2300c. With the 210 and 230 being the earliest, and 2300c being the final incarnation before the entire line was dropped in early 1997.