L-cysteine HCl monohydrate is the hydrochloride salt of L-cysteine, a semi-essential, sulfur-containing amino acid and is an important structural component in many proteins. Supplementation of L-cysteine supports the immune system and healthy metabolic processes as a component of protein synthesis, in addition to supporting cellular structural components in the form of the antioxidant, glutathione. Product: L-Cysteine Hcl Mono CAS NO.: 7048-04-6 Molecular Formula: C3H8ClNO2S.H2O Molecular Weight: 175.63 Supplier: premium ingredient co.,ltd