Case of 24 - Calibration Solution | 250ml 7.0 + 4.0

This bundle comes with the following:

 12 - 250ml 7.0 buffer solution

12 - 250ml 4.0 buffer solution

Solution is compatible with any digital pH pen that calibrates to 7.0 and 4.0.

Ingredients: Potassium Hydrogen Phthalate