Hanna pH 7.0 Calibration Solution 500ml crystal star Two outlets collectively support up miscnutes Two outlets collectively support up to 1100W to control plugged in devices together or independently The Anden A210V1 Dehumidifier model was developed to maintain a stable saturation point and a homogeneous atmosphere around your plants Air tight bottle with tamper proof sealEnsures quality and freshness of solutionColor coded label for easy pH buffer value identificationEasy to identify different buffer valuesSolution does not contain any dyes that may stain the reference cell of a pH electrode 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