The 737-900ER is the newest and biggest Boeing 737. It was made so that it could replace the 757-200. It was also made to be a rival to the Airbus A321. 180 passengers can fly on a 737-900ER with two classes. 215 passengers can fly if the plane only has one class. The -900ER can carry more fuel and has winglets. It can fly for around 3200 nm. The 737-900 is no longer made; Boeing only makes the 737-900ER now.