MULTI ION  IC STANDARD - 6 COMPONENTS (Lithium (Li+) 0.5 mg/L; Sodium (Na+)2 mg/L; Ammonium (NH4+) 2.5 mg/L;  Potassium (K+) 5 mg/L;  Magnesium (Mg2+) 2.5 mg/L; Calcium (Ca2+) 5 mg/L in 0.1% Nitric Acid) - traceable to NIST 
            
            
                Expiry: 6 months after opening