- The future of Vitamin C has arrived. Potent-C™ Power Serum unleashes the strength of THD ascorbate, an ultra-stable scientific breakthrough ingredient 50 X more powerful than traditional Vitamin C. Packed with a jaw-dropping concentration of 20% Vitamin C, the serum’s efficacy is amplified by the addition of two ultra-powerful antioxidants (3% Vitamin E and 2% Ferulic Acid), delivering a complete and advanced anti-aging, firming and brightening treatment. This rich moisturizing serum is a must to help improve the look of fine lines, wrinkles, firmness, uneven skin tone, texture and brightness. Fragrance-free and non-irritating. Apply 1-2 pumps to clean, dry skin. For best results, use twice daily on face, neck and back of hands. For external use only.