As this is a powder, in a sealed packet there is no
The contents will make up to 250ml each.
Just add water or distilled water
Use for PH tester measure calibration solution
Product description: 1. Immerse the electrode in pH 6.86( under the temperature of 25 ℃) standard buffer solution of phosphate, and gently shake the electrode.
2. Regulate the trimmer with a screwdriver until the buffe