Enter Air (E4, Warsaw Chopin) has been revealed as an Unidentified Customer which ordered an additional B737 from US manufacturer Boeing (BOE, Washington National).

The Polish carrier announced plans to acquire two B737-800s and two B737 MAX 8 aircraft during the Paris Air Show 2015 at Paris Le Bourget. The order, worth more than USD400 million at current list prices, had also been attributed to an unidentified customer prior to that announcement.