Premium quality buffer solutions by Hanna Instruments. Hanna calibration buffers have the lot number and expiration date clearly marked on the label and are air tight with a tamper-proof seal to ensure the quality of the solution. Hanna’s line of calibration buffers have been specially formulated to have an expiration of 2 years from the date of manufacture for an unopened bottle

Accuracy of +/- 0.01 pH @ 25°C

Temperature chart of the actual pH value at various temperatures printed on each bottle.