Use to store your pH meter electrode between use. This solution is designed to keep your electrode sensing membrance and reference junction clean and unclogged and ready for use. Store your electrode directly in a small cup of solution or saturate a sponge in the cap of your meter for storage between use. This will prevent your permeable glass membrance from becoming dry and from mineral deposists clogging the surface. This solution is designed to equalize the osmotic pressure of the reference solution in your meter juction to keep the reference solution from seeping out and prematurely aging your meter. Should your electrode membrane dry out soak it in this solution for at least two hours before use. NEVER store an electrode in distilled or deionized water.