ThinkPad i series
A wide variety of notebook PCs were sold as part of i Series, from low-cost consumer models to ultraportables nearly identical to X Series. The first wave (type 2611) uses a different power inlet than most ThinkPads: 19 volt supply and a 5.5/2.1mm connector. Wave two (type 2621), and all newer models in the series, have the ordinary 5.5/2.5 16V power connector. The i Series 1400 and 1500 lines are classic budget models manufactured by Acer under license from IBM.