Vitamin C Suspension 23% + HA Spheres uses direct vitamin C and hyaluronic acid to help visibly reduce signs of aging by brightening and balancing uneven skin tone. This water-free formula provides 23% pure L-Ascorbic Acid which remains completely stable due to the absence of water. What’s more? This water-free formula is supported with spheres of hyaluronic acid for added hydration. Note: The slightly granular texture of this product is due to the vitamin C powder being suspended in an oil-like base and therefore each application requires a few seconds to feel absorbed by the skin. If desired, this formula can be diluted in a cream base per application to allow the skin to build tolerance over time. We do not recommend combining this product in the same regimen with Niacinamide 10% + Zinc 1%. 100% Niacinamide Powder. EUK 134™ 0.1%. Direct Acids. Peptides. or Retinoids. How to Use: The Ordinary recommends performing a patch test prior to incorporating a new product into your skin care routine. Apply a small amount to face in the AM or the PM. A slight tingling sensation can be expected after application.