This Micro Essential® Tri-Chek buffer set provides calibrated and pre-weighted amounts of buffer powders in capsules at three pH values: 4.0, 7.0. and 10.0. A correctly calibrated pH meter will check all three points. This set furnishes the materials needed for reliable pH meter standardization and verification. The buffer powders in the package are stable and will keep indefinitely. The powders dissolve rapidly in water to give fresh reliable standards in just a few minutes. The included color keyed buffer preservative will prolong the useful life of the solution. A few drops of this preservative added to the buffer solution is an effective mold inhibitor and automatically tints each solution to its own value color. Each capsule contains sufficient powder to make 100ml of buffer solutions. Per each. Micro Essential Labs® #: CC-471V.