Phonetic transliteration: 肖 ('sh-'), 特 ('-or-'), 斯 ('-ts/s'). Characters are sound-only, not meaningful here. The combination 特斯 is recurrent in Western-name renderings (compare 特斯拉 Tesla, 福斯特 Foster).
memory
Note: the character 肖 has two readings - Xiào (used in surnames, abbreviations of 萧) and xiāo (in 肖像 'portrait'). In transliterations, the surname reading Xiào is the convention.