Lab tests came back a little lower than I thought they should, but still positive. 236mg/ml. Now this is within 6% of label claims which isn't that bad when you put it that way. I just recently saw Schering Primo tested at 96mg/ml which was off 4% of label claims and they are a major pharmaceutical company. For the price, you can't complain too much. This was only for lot # 31348. Future lots will be tested as well and hope to be within closer range, if not over label claims.