pH Calibration & Maintenance set - pH 4,7,10, Potassium Chloride pH Calibration & Maintenance set - pH 4,7,10, Potassium Chloride Bottles are all labeled with contents including CAS numbers. Tolerance +/ 0.01 @ 25 Degrees Celsius This kit has an instructions and material safety data sheet (MSDS) packet for product information and handling procedures, and is suitable for age 13 and older with adult supervision. For laboratory use only. Not for Drug, food or household Use. Keep out of reach of children.