It features two drives (totaling 6 or 4 TB, depending on the product version) that can be configured in a RAID array; in that case, all data is automatically mirrored and can be recovered if one of the drives fail (but effective drive space is halved).
ɪt fˈiːtʃɚz tˈuː dɹˈaɪvz tˈoʊɾəlɪŋ sˈɪks ɔːɹ fˈoːɹ tˌiːbˈiː, dᵻpˈɛndɪŋ ɔnðə pɹˈɑːdʌkt vˈɜːʒən ðæt kæn biː kənfˈɪɡɚd ɪn ɐ ɹˈeɪd ɚɹˈeɪ; ɪn ðæt kˈeɪs, ˈɔːl dˈeɪɾə ɪz ˌɔːɾəmˈæɾɪkli mˈɪɹɚd ænd kæn biː ɹᵻkˈʌvɚd ɪf wˈʌn ʌvðə dɹˈaɪvz fˈeɪl bˌʌt ɪfˈɛktɪv dɹˈaɪv spˈeɪs ɪz hˈævd.