Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Hydropeptide Firma-Bright 20% Vitamin C Booster Versus Kiehl's Powerful-Strength Vitamin C Serum

This brightening serum is formulated around Sodium Ascorbyl Phosphate and Niacinamide to brighten dull-looking skin and soften the look of wrinkles. This anti-aging serum is formulated around Ascorbic Acid and Ascorbyl Glucoside to soften the look of wrinkles

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  • This brightening serum is formulated around Sodium Ascorbyl Phosphate and Niacinamide to brighten dull-looking skin and soften the look of wrinkles.
  • This anti-aging serum is formulated around Ascorbic Acid and Ascorbyl Glucoside to soften the look of wrinkles and brighten dull-looking skin.