While traveling, I had placed approximately 50 grams of PMC in a plastic bag and put it in the ClayVault and then forgot about it. Three months later, while digging through my travel toolkit I found the ClayVault. When I opened it I couldn't believe I had left this much clay out and thought for sure that it had dried up. I was so amazed and pleased to find that the clay was just as moist as when I first put it in the ClayVault! I won't store any of my clay long term in anything but the ClayVault. Thanks to the inventor of this amazing tool!