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• ● Liquid standards with bovine protein
• ● Remarkable optical clarity
• ● Contains esterified and free cholesterol from bovine serum
• ● Known concentrations verified against available NIST Standard Reference Material
• ● For calibration or calibration verification
• ● Constant protein content, pH and ionic strength across concentration levels
• ● Prepared without surfactants, glycol or azide
• ● Stable 21 months from date of manufacture
• 
  

Extended range available. See Level F below.