It is narrated from Sayyiduna Khuzaymah bin Thabit (may Allah be pleased with him) that a Bedouin asked about wiping over leather socks, and he (peace and blessings be upon him) said: "Three days and three nights." The Companions said: We thought that had he asked for more (time), he (peace and blessings be upon him) would have given more.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 1321