The sandals of the Messenger of Allah [SAW] had two straps.  

أَنَّ نَعْلَ رَسُولِ اللَّهِ ﷺ كَانَ لَهَا قِبَالاَنِ  

"The sandals of the Messenger of Allah [SAW] had two straps."  

كَانَ لِنَعْلِ رَسُولِ اللَّهِ ﷺ قِبَالاَنِ