Hello: I am a professional manufacturer of chondroitin sulfate and chondroitin sulfate health care product. The quality and lasting period is long and good. About our chondroitin sulfate we have many kinds . Origin form bovine , porcine, chicken, shark. The assay: 85% , 90%, 95%. As a professional manufacture of chondroitin sulfate for almost 11 years. We guratten that all our products are made in 100% qualified materials with competitive prices. If you are interest in it , I am gald to introduce more details to you , please feel free to contact me .