The Restylane line of products is formulated to act like your body's own naturally occurring hyaluronic acid, restoring volume to your skin. Restylane Silk, Restylane and Restylane Lyft use our innovative NASHA technology. This gives each product a unique particle size for tailored treatment. Restylane Refyne and Restylane Defyne are flexible hyaluronic acid gels designed to give you the flexibility to show your natural range of facial expression.