[71] Now at that time a certain bhikkhu, having tied his sandals together with his waistband (kāyabandhana), entered the village for alms. A certain lay follower (upāsaka), while paying homage to that bhikkhu, struck his head against the sandals. That bhikkhu was embarrassed. Then that bhikkhu, having gone to the monastery, informed the bhikkhus of this matter. The bhikkhus informed the Blessed One of this matter. "Bhikkhus, I allow a bag for sandals (upāhanatthavikā)." There was no shoulder strap (aṃsavaddhaka) … "Bhikkhus, I allow a shoulder strap and a string for tying (bandhanasuttaka)."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.