World’s lightest 14″ business ultrabook Ultrathin. Ultralight. Ultratough. For the average Ultrabook these attributes may sound like a contradiction. But the new X1 Carbon is far above average. It features a carbon-fiber reinforced chassis and passes durability tests in extreme environments. Plus, it delivers more than all-day battery life, includes faster, more powerful storage performance, and has innovative docking options available, including wireless.