From the price you buy to see you buy is genuine Dong'a Colla Corii Asini, genuine Colla Corii Asini surface color uniformity - hard and brittle - translucent - feel delicate and smooth - with poor quality Colla Corii Asini than easily soluble in water. The kind you see on the Internet is the poor quality of the kind, in the Anguo market is about 18 dollars a kilogram. Brand of course is the Dong'a good, above the anti-counterfeiting query phone number, the effect is good Colla Corii Asini is the top of the blood but if you add some of the qi nourishing blood of the traditional Chinese medicine effect will be better!