pH Buffer solution with measuring chamber, pH 4,00 0,01, 500 ml

Bottle with a separate measuring chamber, "twin-neck". No other containers are required during the calibration process and subsequent cleaning thereof, preserving the purity of the buffer solution. Colored solutions to prevent mistakes. Certificates traceable to SRM from NIST. Variation table of pH / temperature on the label. Use within 12-15 months of opening