This is the Original C Serum Face Serum- a Registered USA Trademark of Repechage. Pure Natural Formula. 100% Natural. Highly Concentrated Seaweed Formula. Nourish your skin daily with essential vitamins, minerals & amino acids. C-Serum, short for cytoserum, is a highly concentrated seaweed extract rich in vitamins, minerals, amino acids, trace elements & phyto-hormones necessary ...