Iyad bin Abdullah (may Allah have mercy on him) says that sadaqat al-fitr (the zakah of Ramadan) was mentioned in the presence of Sayyiduna Abu Sa'id (may Allah be pleased with him), and he said: I give only what I used to give in the time of the Messenger of Allah (peace and blessings be upon him): a sa' of dates, or a sa' of wheat, or of barley, or a sa' of cheese. A man from the people said to him: Or two mudds of wheat? He said: That is the valuation of Sayyiduna Mu'awiyah (may Allah be pleased with him); I neither accept it nor act upon it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7702