United Airlines confirmed Friday that it will add four more seats to its regional jets, through the reconfiguration of cabins and the addition of thinner seats.

The Chicago-based airline announced on Thursday it will install a thinner seat design on about 500 planes that fly throughout North America, mostly regional jets.

On Friday, a spokeswoman confirmed details of a note posted on a popular online aviation blog that detailed a reconfiguration of the airline’s most popular regional jet, the CRJ700. The company plans to cut the size of the more-expensive and roomier Economy Plus section in half to 16 seats, while the number of seats in coach will rise to 48 from 28. First class will remain the same with six seats.

In total, the planes will have 70 seats up from 66. The legroom for each seat will remain the same, United said.

The ability to add more seats — even just four — will be a revenue driver for the airline because it can carry more customers without adding flights. Although at the same time, it will have more of the cheaper coach seats and less of those economy plus seats passengers have to pay a premium for.

The thinner seats are much lighter than the ones they are replacing, United said, which will also allow it to save on fuel costs.

The seats appear to be the same width as United’s current ones, but the backs and bottoms are not as thick. The Chicago-based airline refused to comment on the actual dimensions of the seats and how they compare to the current ones.

United says the seats provide more ergonomic features and cushioning for fliers, as well as extra seatback storage. They will also allow for a more consistent look across its domestic fleet, a spokeswoman said, through the addition of these new leather seats.

United is introducing the new seat design first on its regional jets operated by SkyWest Airlines, the smaller aircraft that run many of the shuttle flights between major cities, often frequented by business travelers. It expects to add the new seats on the rest of the regional fleet next.

Ultimately, United plans to install 60,000 seats on more than 500 aircraft, 400 of those in two years.

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