"I said to Ibn 'Umar: 'I see you are wearing Sibtiyyah sandals, [1] and you performed Wudu' in them.' He said: 'I saw the Messenger of Allah ﷺ wearing then and performing Wudu' in them.'" [1] Made of hairless, tanned leather. (Using translation from Nasāʾī 117)  

قُلْتُ لِابْنِ عُمَرَ رَأَيْتُكَ تَلْبَسُ هَذِهِ النِّعَالَ السِّبْتِيَّةَ وَتَتَوَضَّأُ فِيهَا قَالَ «رَأَيْتُ رَسُولَ اللهِ ﷺ يَلْبَسُهَا وَيَتَوَضَّأُ فِيهَا»