Effective protective serum for everyday use: ISDINCEUTICS FLAVO-C ULTRAGLICAN AMPOULES ISDINCEUTICS FLAVO-C ULTRAGLICAN AMPOULES from Isdin GmbH offer optimal protection against free radicals thanks to their special vitamin C formula. These ampoules contain Ultraglican, an effective combination of proteoglicans and pre-proteoglicans that helps the skin retain moisture and improve its stability. Application recommendation for optimal results For maximum effect, apply the ampoules to cleansed, dry skin every morning. Shake well before use. Use one-third of an ampoule and apply the serum to the face, neck, and décolleté, avoiding the eye area. Gently massage the product in until fully absorbed. Once opened, the contents of the ampoule should be used within 48 hours to ensure effectiveness.