bˈɑːks spɹˈɛdz ɑːɹ jˈuːʒuːəli ˈoʊnli ˈoʊpənd wɪð jˌʊɹɹəpˈiən ˈɑːpʃənz, hˌuːz ˈɛksɚsˌaɪz ɪz nˌɑːt ɐlˈaʊd ʌntˈɪl ðɪ ˈɑːpʃənz ɛkspɚɹˈeɪʃən.
Box spreads are usually only opened with European options, whose exercise is not allowed until the option's expiration.