Narrated Ibn Buraidah:
from his father: "An-Najashi gave the Prophet (ﷺ) two black plain Khuff. So he wore them, then he performed Wudu and wiped over them." (TR)
English reference (TR): Vol. 5, Book 41, Hadith 2820 (TR)
Arabic reference (TR): Book 43, Hadith 3052 (TR)