Since 1947 Well-Retained Gentle & Non Acidic Immune Support Non GMO Halal Gluten, Wheat & Dairy Free Suitable for Vegetarians Certified Gluten-Free K-Parve Dietary Supplement Ester-C Plus is exclusively formulated by Solgar and provides a patented, pH neutral (non acidic) Ester-C Vitamin C that is gentle on the stomach. The Vitamin C metabolites in Ester-C positively impact the retention of Vitamin C in cells, providing additional benefits. A special manufacturing process is employed to form a unique calcium ascorbate metabolite complex. This well-retained complex further incorporates natural bioflavonoids and acerola berry along with rose hips fruit.