Abu Karayb, Muhammad bin al-'Ala' محمد بن العلاء - أبو كريب · The Book of Purification

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

"I heard 'Imran bin Husain (say) that the Prophet (ﷺ) saw a man who was by himself and did not pray with the people. He said: 'O So and so, what kept you from praying with the people?' He said: 'O Messenger of Allah, I have become Junub and there is no water.' He said: 'You should use earth for that will suffice you.'"