This serum contains 10% azelaic acid and helps even skin tone and bring out clarity. - Brand: Cos De Baha - Product Name: AZA 10 Serum - Ingredients: Azelaic Acid 10% - How to Use: Apply 1-2 drops in the morning or evening - Expiration Date: November 22, 2025 The remaining amount is as shown by the red line in the photo. The area around the bottle opening has some white residue, but this is due to the ingredients and should not be a problem. It is close to the expiration date, so it is being offered at a low price.