Formulated to provide precise pH values, these buffer solutions which are standardised against N.I.S.T. certified reference samples, are ideal for calibrating electrodes and pH meters. The buffers are colour-coded to avoid error and accurate to within ±0.02 pH at 25°C. Each buffer contains a preservative/mould 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 solution is 1 Year from date of manufacture.