111Skin Y Theorem Repair Serum NAC Y2 in Beauty: NA. 111Skin Y Theorem Repair Serum NAC Y2 in Beauty: NA. Originally created to treat skin after surgery, 111SKIN's Y Theorem Repair Serum aids the healing of irritated, damaged skin through cutting-edge ingredients. Designed in collaboration with space scientists, the formula contains proprietary NAC Y2 complex to provide skin with the optimum conditions for collagen, elastin, and hyaluronic acid production. This innovative anti-aging serum reduces the appearance of fine lines and wrinkles, builds volume, and rejuvenates the complexion to reveal younger, plumper looking skin.. Calendula extract heals and soothes the skin. Amino acids improve skin elasticity. Aminocaproic acid heals, prevents scarring, calms, and soothes the skin. 1.01 fl oz. Massage serum sparingly onto the face and neck with a gentle patting motion. Follow with the Space Anti Age Day Cream or Nocturnal Eclipse Recovery Cream and Space Defence Bright Eye Lift Gel. 111R-WU24. YT30. Working in collaboration with space scientists responsible for the well-being of astronauts, renowned cosmetic surgeon Dr. Yannis Alexandrides developed the patented NAC Y2 formula that runs through the core of his highly effective skincare line. Named after his Harley Street, London clinic, 111SKIN's cutting-edge products feature potent healing ingredients designed to promote a youthful and radiant appearance while offering unprecedented protection against environmental damage.