Minimizes problems in pure water pH measurement. Includes pure water “pHisa” adjuster pH additive for increased ionic strength. Special set of diluted buffers containing same background of pHiX adjuster as sample also included, resulting in neglible net effect on pH. A good quality glass electrode, such as the Orion Ross electrode 657-800-02 or 657-800-04, is recommended for measurement. Kit includes four 475 ml bottles of Low Ionic Strength pH buffer A, 6.97; two 475 bottles L.I.S. pH buffer B, 4.10; two 50 ml bottles pHiX® adjustor; one 1 ml syringe; one holding tray; instruction card, and application procedure pamphlet.