The non-approximant consonants of Jeju correspond to the nineteen non-approximant consonants of Standard Korean, and Jeju displays the three-way contrast between stops and affricates characteristic of Modern Korean. Whether the voiced glottal fricative , absent in Standard Korean, exists as a phoneme in Jeju or merely as an allophone of remains disputed. A 2000 acoustic and aerodynamic study of eight native Jeju speakers concludes that "the consonants of the two languages seem to be the same in every respect... the phonetic realization of all consonants are the same as those found in [Seoul Korean."