100ml

pH probes require periodic calibration to ensure users continue to obtain accurate pH measurements. OF Calibration solutions pH 4 & pH 7 are specifically made to allow users to calibrate their probes to the highest possible accuracy. Calibration should be performed with at least two standard buffer solutions. As pH 7 is essentially, a “zero point” calibration ( similar to zeroing a scale or balance ), calibration at pH 7 followed by calibration at pH 4 as the second point of reference will enable users to perform a more accurate two point calibration.