Boeing and China’s Okay Airways announced a $1.3 billion commitment here yesterday covering twelve 737s, including eight 737 Max 8s, three Max 9s and a single 737-900ER. The deal marks the first 737 Max 9 order by a Chinese airline and boosts Okay’s Max portfolio to 17 airplanes.

The contract also gives Okay rights to exercise options for another eight 737 Max 8s. It remains subject to approval of the Chinese government and will appear in Boeing’s official order backlog once the sides clear all “contingencies.”

The first private airline in China, Okay launched 737 operations in 2005 and remains the country’s only 737-900ER operator. Its fleet of fourteen 737-800s, three 737-900ERs and a Boeing 737-300 freighter serves more than 100 domestic and international routes.

Appearing here at the Singapore Airshow yesterday with Boeing Commercial Airplanes CEO Ray Conner, Okay Airways chairman Wang Shusheng attributed several years of profitability at his airline largely to Boeing’s support of its 737 fleet.

“We greatly value the ties we have built over the years with Boeing,” said Wang. “The 737 has made Okay Airways’ operations profitable for many years. I’m sure it’s going to be a great asset to ensure Okay Airways’ future development.”

Now occupying six operating bases, Okay plans to transfer its main base from Tianjin Binhai International Airport in Beijing to a new airport under construction in the city scheduled for opening in 2018. Wang added that Okay plans to increase the size of its fleet to 80 airplanes by 2020.