5 components: 1000mg/l each of Calcium (Ca2+) Magnesium (Mg2+) Potassium (K+) Iron (2+) (Fe2+) Sodium (Na+) in Water CRM, ISO 17034 and ISO 17025 Conservation 24 months. (12 months after opening) Store under normal laboratory conditions, at t 1 * 100 mL