Aircraft N904NK is one of five A320NEOs (or A320-200Ns) currently in service with Spirit Airlines. Both Spirit and Frontier are the only U.S. operators of the A320NEO (as of now).

The unique feature of the NEOs is the addition of new engine options! The new engines can be either Pratt & Whitney PW1100-series powerplants or CFM International's new LEAP-1 powerplants. These new options are not only more fuel efficient and more powerful, they are also the quietest high-bypass turbofans I've ever heard.