WeightWorld OPC (French Grape Seed Extract) contains 1000 mg of French grape extract, of which 950 mg is OPC. French grape extract is rich in antioxidants, such as phenolic acids, flavonoids, anthocyanins and oligomeric proanthocyanidin complexes (OPCs). Oligomeric proanthocyanidin complexes (OPCs) are a group of natural plant compounds, specifically flavonoids found in high concentrations in grape seeds. OPCs are known for their powerful antioxidant properties and have been studied for their possible health benefits.