Dafin No. 4 was bred from the Pearl Heart seeded hybrid of Wenzhou Mandarin "Jintian Zaosheng" and "Bashuo" in Japan. It has a moderate tree potential and was introduced by Huazhong Agricultural University.
In Chongqing, coloring began in mid and late August and completely colored in mid and late September. The peel is dark after maturity, orange red when fully mature, flat and round in shape, with an average fruit weight of 125g and not easy to float. The sugar degree can reach 10 ° in the first ten days of September and 13 ° in the middle and late ten days of September. It tastes sweet and sour, refreshing and high-yield.