DescriptionFormulated to provide precise pH determinations, these buffer solutions which are standardized against N.I.S.T.-certified reference samples, are ideal for calibrating electrodes and pH meters. The buffers are color-coded to avoid error and accurate to within ±0.02 pH at 25°C (77°F). Each buffer contains a preservative/mold inhibitor and a shrink-sealed cap to prevent contamination and leakage. Temperature compensation charts are included with each buffer solution. The shelf life of the buffer solutions are 1 Year.