Ƙirƙiri wani nau'i mai mahimmanci na wannan jumla Zaɓin da aka saba shine don 'I' ya zama marar iyaka kuma 'U' ya ƙunshi dukkan sassan cofinite na 'I'.
Tabbas, wani nau'i mai rikitarwa na jumla shine "Zaɓin da aka saba shine don '' I 'ya zama mara iyaka kuma' U 'ya ƙunshi dukkan cofinite subsets na' I ',' in ba haka ba ultrafilter shine babba, kuma ultraproduct yana da isomorphic ga ɗaya daga cikin abubuwan. "