That the Prophet ﷺ said: "Whoever purchases an animal that has not been milked, then he retains the option for three days. If he returns it, then he is to return with it a Sa' of food, not Samra' " (Using translation from Tirmidhī 1252)
عَنِ النَّبِيِّ ﷺ قَالَ مَنْ اشْتَرَى مُصَرَّاةً فَهُوَ بِالْخِيَارِ ثَلَاثَةَ أَيَّامٍ فَإِنْ رَدَّهَا رَدَّ مَعَهَا صَاعًا مِنْ تَمْرٍ لَا سَمْرَاءَ