Over the rest of the year, all aircraft in Southwest’s fleet will be retrofitted to accommodate the new seats with up to 5 inches of expanded legroom, the company said in a statement.

Southwest Airlines unveiled new fare bundles this week, giving fliers a first look at how different fares will determine seat selection, checked bag charges, refunds and more. The new bundles are a shift from the usual tickets that range from the cheapest Wanna Get Away fares to the more luxurious Business Select fares.