Cellex-C® Serum for Sensitive Skin. This lightweight, oil-free, aqueous solution contains the full complement of Cellex-C Complex signature Ingredients. This formulation has been buffered to a 3.3 pH to accommodate highly sensitive skin types. Regular use will reduce the appearance of fine lines, wrinkles, age spots, and sagging skin. Generally, improvements in the overall appearance of the skin can be seen in 8-12 weeks of daily use. Suitable for sensitive skin. 1 fl. oz.