What can I say, I went in to GNC w/just the thought of looking ! the clerk greeted me, ask if he could help with anything! very nice, I told him I was looking ! somehow we got on the subject of my hurt knee, he recommended shark cartilage pills! made me think what if these things work!, he even offered a refund if I felt they were not working!, very, very good customer service! soft sell!, I recommend going here treated good!,