An innovative valve system is what makes the Evak Mini Airtight Stash Jar such an important asset for any storage needs. The longer your dry herbs and tobacco are exposed to air, the faster it dries out and loses flavor. With Prepara's twin valve system, when you insert the rubberized top into the stash jar you are actually forcing air out while you push down. This is better than an airtight lid as they can still trap stale air in with your goods. A simple push down seals your dry herbs or tobacco, and an easy pull up lets you access them. With only two steps it doesn't get any easier. The jar itself can hold a 1/4 oz of tobacco with no air bubbles wasting any space and is dishwasher safe. Keep whatever you are storing not only airtight, but as fresh as can be!