Yan Yu No. 4, the fruit is round in shape, with a slightly concave top. The single fruit weighs 200 grams, and large fruits weigh around 250 grams. It is a white-fleshed plum with firm flesh and a sweet, crisp taste. The soluble solids content is about 15%. In terms of quality, it has no core, is highly productive, has a large flower shape, self-fertilizes, and in Zhengzhou region, the mature fruit has nearly fully red skin (at the Xinxiang base of Zhengguo Research Institute). The single fruit weighs 200 grams, and large fruits weigh over 300 grams. The soluble solids content is 12.6% to 15.3%.