pH Calibration Buffers Colour Coded pH 4.01 (Red), pH 7.0 (Yellow) pH 10.0 (Blue) Pack Sizes: 250ml, 500ml, 1L, 5L Simply select your required pH Value and Pack Size from drop down pH Buffers used for calibrating pH meters need to be a known value of a certain pH, our buffers (manufactured in Manchester) are tested to a pH accuracy of 0.01 pH. - - Colour Coded for ease of identification and two values are required in a TWO point calibration process, pH 4.01 (Red) and pH 7.0 (Yellow). - - pH 10.01 is used in a Three Point calibration or as an alternative to 4.01/7.0 in a two point calibration. - - When calibrating it is advisable to only use a small amount (50ml) of each buffer in two separate containers, calibrate the meter and discard buffers same day to prevent.
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