옷 has written final ㅅ. When you say 옷 alone and stop, its pronunciation is represented as [옫]. Brackets show sound; they do not replace the correct spelling.
Written word
옷
Written final: ㅅ
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Isolated pronunciation guide
[옫]
Ending-sound group: [ㄷ]
Read the word alone and pause. Brackets guide pronunciation; they do not replace spelling.