Abu Zaid 'Amr ibn Akhtab al-Ansari told me:
“Allah’s Messenger (Allah bless him and give him peace) said to me: ‘O Abu Zaid, come close to me and stroke my back!’ I duly stroked his back, whereupon my fingers touched the Seal. I said: ‘What is the Seal?’ He said; ‘Intertwined hairs.’”