"The messenger of Allah ﷺ was asked during the campaign of Tabuk about the Sutra of one who is praying. He said: "Something as high as the back of a camel saddle." (Using translation from Nasāʾī 746)  

سُئِلَ رَسُولُ اللهِ ﷺ فِي غَزْوَةِ تَبُوكَ عَنْ سُتْرَةِ الْمُصَلِّي فَقَالَ «مِثْلُ مُؤْخِرَةِ الرَّحْلِ»