1 x ANUA Niacinamide 10% + TXA 4% Dark Spot Correcting Serum (30ml) in a sealed bottle with a dropper. 4% Tranexamic Acid (TXA). Product Type: Dark Spot Correcting Serum. 10% Niacinamide. Perfect for those with acne scars, sunspots, or discoloration, this lightweight serum absorbs quickly and is suitable for all skin types.