Spirit Airways sells the massive Entrance Seat onboard its aircraft, which is similar for the seats in US domestic first class, but there is no other difference in company or amenities for patrons seated in that part. Having a Going Elite membership, it is possible to entry the cheapest premium class https://businessflightshop.co.uk/blog/catch-the-best-flights-to-seoul-korea-from-uk-to-spend-a-wonderful-vacation/