Adequate skin hydration is critical for maintaining healthy skin. Moreover, dehydration, together with reduction in cell renewal, loss of radiance, elasticity and firmness, is involved in skin aging. Injectable anti-aging products have been widely used for aesthetic improvement of the skin. In recent years, new filler products made from High Purification Technology Polynucleotides (PN HPTTM) have been developed and are now being used in Europe. PN HPTTM has a consolidated utilization in the aesthetic field and recently, specific guidelines in their utilization have been implemented. Polynucleotides (PNs) are polymeric chains formed by purines, pyrimidines, deoxyribonucleotides, and deoxyribonucleosides that can be found in cells throughout the human body. PNs have viscoelastic properties and the capability to bind, reorganize and orientate a high concentration of water molecules, creating 3D gel that undergoes an enzymatic cleavage. On this basis, polynucleotide-containing products act as short-time temporary fillers to produce a volumizing effect and exert a lubricant and moisturizing action, due to the high concentration of water molecules. Moreover, they maintain for a long time the moisturizing and viscoelastic effect. A recent report which summarizes the findings and recommendations issued from the Italian Scientific Board of aesthetic physicians, supports the use of PN-HPT. In this context, the Sponsor has developed PN30, a soft-tissue filler containing PN-HPT (at a concentration of 30 mg/ mL) as functional ingredients which help improve skin turgor and elasticity due to their moisturizing and viscoelastic properties. PN30 is a new device with no history of marketing but based on a similar product CE marked developed and sold by the Manufacturer with less amount of PN (2%). Therefore, the aim of this pre-market, twostages, monocentric, interventional, single-arm, clinical investigation is to evaluate the safety and the performance of PN30 (RDM16) for the improvement of skin hydration. The clinical investigation is planned as an adaptative two-stages study. The planned procedures will be the same for both stages. The primary objective/endpoint of STAGE I will be to evaluate the safety, while the primary objective/endpoint of STAGE II will be to evaluate the performance of the device.