Europe’s largest travel group, TUI Travel, has confirmed an order for 60 Boeing 737 MAX jets with an option and purchase rights to buy another 90, adding that it has it has obtained “significant discounts” on the price of the aircraft and spare engines.

The order, which was first announced at the end of May and is still subject to shareholder approval, consists of 40 737 MAX-8s and 20 of the larger -9.

Speaking at the Paris air show, TUI Travel’s CEO Peter Long said the group secured a significant discount to the list price of each aircraft “through various concessions, allowances and support from Boeing.” It also secured “substantial price concessions” against the list price of the eight spare Leap-1B engines, which it is buying from CFM International.

The value of the 60 Boeing 737 MAX aircraft is $6.1 billion at current list prices.

The delivery period for the 60 committed aircraft will start in January 2018 and run until March 2023.

TUI Travel owns and operates six European airlines—Thomson Airways, TUIfly, TUIfly Nordic, ArkeFly, Jetairfly and Corsair—with 141 aircraft in total. Five of these carriers operate 114 narrowbody aircraft between them, serving short- and medium-haul routes.

About 80% of the group’s airline passengers traveled on narrowbody aircraft on such routes for their holidays during the last financial year.

TUI Travel will roll over its entire short- and medium-haul fleet with 737-800s and the MAX as leases on existing aircraft expire, according to Long. Belgian subsidiary Jetairfly added five new 737-800s this year. The group recently took delivery of the first of 13 Boeing 787s it has on order.