The 737-800 is a longer version of the 737-700. It replaces the 737-400. The -800 was finished in 1994. It entered service with Hapag-Lloyd Flug (now TUIfly) in 1998. 162 passengers can fit into a 737-800 if it has two classes. Up to 189 can fit into a 737-800 if it only has one class. Its main rival is the A320.