The manufacturers of Yueer and Shuangwhale are Qingdao Shuangwhale Pharmaceutical Co., Ltd., because the manufacturers change the packaging of goods from time to time, Yueer and Shuangwhale have become Shuangwhale.
Qingdao Shuangjing Pharmaceutical Co., Ltd. is a high-tech enterprise dedicated to innovative research, development, production and sales of drugs. The company, formerly known as Qingdao Cod Liver Oil Factory, was established in 1950. It is the first vitamin production enterprise and cod liver oil production enterprise in New China.