It is narrated from Sayyiduna Ubayy bin Imarah al-Ansari (may Allah be pleased with him) - and the Messenger of Allah (peace and blessings be upon him) had prayed in his house towards both qiblahs - he said: I said: "O Messenger of Allah! May I wipe over the leather socks (khuffs)?" He (peace and blessings be upon him) said: "Yes, one day." I said: "O Messenger of Allah! And two days?" He (peace and blessings be upon him) said: "Yes, and three days too." I said: "O Messenger of Allah! And three days?" He (peace and blessings be upon him) said: "Yes, and as long as you wish."
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 542