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GroLine pH 4.01 Calibration Buffer – 20mL Sachets (25 Pack)



The GroLine pH 4.01 Calibration Buffer solution is designed to quickly and accurately calibrate pH meters. Over time, pH meters will deviate from their calibrated settings resulting in faulty readings making it important to calibrate your meter often. Hanna Instrument provides a simple and quick solution to calibrate your meters, each sachet is portable and comes with just the right amount of solution.

  • Supplied with Certificate of Analysis
  • Reported values are accurate to +/- 0.02 pH @ 25°C (77°F)
  • Marked with lot number and expiration date

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GroLine pH 4.01 Calibration Buffer

HI70004G is a high-quality pH 4.01 calibration buffer produced in accordance with ISO 3696/BS3978 standards using high purity salts, deionized water, certified weight-checked balances, and Class A glassware in a temperature-controlled environment monitored with certified thermometers. Reported values are accurate to +/- 0.02 pH @ 25°C and are traceable to NIST Standard Reference Materials (SRMs).

Each sealed sachet holds just the right amount of solution making every sachet as fresh as the day it was packaged!

  • Solution does not contain any dyes that may stain the reference cell of a pH electrode.

Light block foil packaging

  • Light-tight packet helps to prevent against degradation by UV light.

One-time use sachet packets

  • Ensures quality and freshness of solution.

Each sachet marked with lot number and expiration date

  • Many Hanna solutions are specially formulated to have an expiration of 5 years from manufacture for an unopened sachet.
Weight 1.5 lbs
Dimensions 6.9 × 6.3 × 3.4 in


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