All materials are analyzed to verify their identity and to determine their purity. All analytes are 99% pure. This standard is accurately prepared by gravimetric technique (+/-0.5%) and all glassware is class A rated. Ampules are purged with nitrogen/argon before and after filling and chilled before being flame sealed. Store ampules sealed as received and process without delay immediately after opening the ampule. Composition: This is, by weight, an equal component mix of: cholesteryl palmitate, tripalmitin, palmitic acid, cholesterol