Hello, it's called bean coat, also called black bean coat It's black bean skin, which is available in general pharmacies now. If not, and you really need it, you can buy black beans, soak them for a few days, and then grind off the skin. Mainly strengthening the spleen and promoting diuresis.

In addition, there is such a record in Compendium of Materia Medica: Black bean coat "is used to treat acne sores, and it is used for mashing children's urinary ash sores."

Farewell.