This hadith has been narrated on the authority of Abu Huraira and Zaid b. Khalid al-Jubani, but in this no merition is made of the words of Ibn Shihab that dafir means rope.
أَنَّ رَسُولَ اللَّهِ ﷺ سُئِلَ عَنِ الأَمَةِ بِمِثْلِ حَدِيثِهِمَا وَلَمْ يَذْكُرْ قَوْلَ ابْنِ شِهَابٍ وَالضَّفِيرُ الْحَبْلُ