Contains one vial each, with 10 capsules per vial of pH 4.0, pH 7.0, and pH 10.0. Each capsule is sufficient to make 100 mL buffer solution. Complete with one vial preservative solution. Powders keep 5 years; prepared solutions keep 3 weeks (or 3 months with preservative added). Preservative contains a pH indicator and colors each buffer solution for easy identification.
