Well, I haven't seen it, but I know a little. I found it online and picked it up. I hope I can help you. In short, Jiugong glue is the best in Ejiao, and the so-called nine dynasties means nine days. This kind of donkey-hide gelatin refining process or one-time refining process takes nine days to refine in Kuya (normal donkey-hide gelatin needs three days and three nights to refine and 49 days to dry), and "tribute gelatin" is specially used to pay tribute to the court. Not all Ejiao can be called "Jiugong Glue", but Ejiao produced in Dong 'e (Gudong 'e, Laodong 'e and present Dong 'e) is the most authentic, and Jiutian Gong Glue is the best in Dong 'e. The production technology and raw materials of Jiugong Glue are very particular, with black donkey skin, Dong 'e well water, traditional ancient processing theory and exquisite and mysterious traditional rubber refining skills (it is said that the only inheritor of China Ejiao's rubber refining skills is Dong 'e Ejiao's chairman) Jiugong Jiaojiao is not only a high-grade health care product, but more importantly, it is to revive the Millennium Chinese medicine culture and the folk culture of winter solstice tonic, so that the nourishing national treasure like Dong 'e Ejiao invented by ancestors can be immortal and passed down.