1x 250 ml pH 4 calibration solution
Standard solutions for calibration and conductivity ... a must in every grower's toolbox.
The Bluelab® calibration and conductivity standard solutions are essential for use with all Bluelab® products.
Bluelab® solutions are manufactured specifically for Bluelab® products and are based on high laboratory standards to ensure that your Bluelab® products last longer and remain accurate.
Of course also great to use with other brands of meters and sensors.