how to store a pH probe

I read somewhere that pH probes do not last forever and that may be so. It was certainly true for the draw full of pH probes, all left to dry, that I found and tested some years back. They needed throwing away or re-activating using alchemy or magic process. But as I today test the pH probes in these containers filled with water, I appear to have a working set of probes. The containers, with an O-ring in the lid, keep the pH probes in working condition for years. Amazingly the containers have yet to leak, even on a long bumpy trip in a suitcase and even after 20 years.