The Hanna Instruments pH 4.01 buffer solution is one of the most commonly used buffer solutions. It is available in small and convenient 20ml sachets. It is highly stable and ideal for those who need an accurate acid indication, especially in water treatment facilities and the food industry.

The single-dose sachets provide:

• Ideal for users who do not calibrate frequently.
• Portability for use anywhere.
• Each sachet is as fresh as the day it was packaged.
• The lightweight packaging prevents oxidation from ultraviolet light.