Negus presented to the Messenger of Allah (ﷺ) two black and simple socks. He put them on; then he performed ablution and wiped over them.

Musaddad reported this tradition from Dulham b. Salih.

Abu Dawud said: This tradition has been narrated by the people of Basrah alone.
Sunan Abi Dawud Book 1, Hadith 155