Vietnam's low-cost airline VietJet Air has taken delivery of the first Airbus A321neo equipped with 240 seats in the new Airbus Cabin Flex configuration.
The aircraft has 30 seats up front with extra legroom, with the remaining 210 seats in the back, according to an image provided by the airline.
VietJet is a pioneer in high-density configurations. In July 2015, it received the first A321neo equipped with 230 seats.

On the A321, the “flex cabin” allows for greater density through a new rear section and a modified door configuration. This shows the removal of the port located forward of the wing and the addition of new overwing emergency exits in the center section.

Compared to the previous A321 variant, the most visible modifications are a new rear section and a modified enger door configuration, where the door located forward of the wing is removed and two emergency exits per wing are introduced in the center section. This will become standard on all A321neos in 2020.
The data shows that VietJet operates 70 aircraft in the A320ceo and A320neo families. The company has orders for 311 aircraft, of which 211 are A320neo family jets and 100 are Boeing 737 MAX 8 models.
Via - Flightglobal