Since 1995, the Kirkland Signature brand has been providing high quality supplements at a great member value. Kirkland Signature vitamins, minerals, and supplements are made from carefully selected ingredients from trusted suppliers. The supplements are manufactured in accordance with the Good Manufacturing Practice standards. Additionally, many of the items are verified by the United States Pharmacopeia (USP) which is an independent, scientific, non-profit organization that sets strict quality and purity standards for dietary supplements.