(102) باب مَوْضِعِ الإِزَارِ
It was narrated that Hudhaifah said:
"The Messenger of Allah [SAW] said: 'The Izar should come to the middle of the shins and the calf. If you insist, then a little lower, and if you insist, then a little further down, but the Izar has no right to (come to) the ankle." This is the wordings of Muhammad.
Reference: Sunan an-Nasa'i 5329
In-book reference: Book 48, Hadith 290
English translation: Vol. 6, Book 48, Hadith 5331