Omega’s calibration buffer solutions and deionized water are pre-mixed and color-coded to prevent errors. All our solutions are standardized against N.I.S.T.-certified reference samples and CAL-Certified, so you can be sure your solution meets all N.I.S.T. guidelines. Our buffering solutions are ideal for calibrating electrodes and pH meters and are accurate to within ±0.01 pH at 25°C (77°F). Each of our solutions contain a preservative/mold inhibitor and a shrink-sealed cap to prevent contamination and leakage and they’re shelf-stable for up to one year. We also carry four popular ranges of conductivity solutions specifically designed for calibrating all conductivity instruments. Stock up on calibration solution from the company you trust for professional calibration equipment.