This Oxo container is a great size for leftover crackers, chips, or other snacks.  Just put them in the container and put on the lid that has a rubber gasket for freshness.  Next push down the popped up circle to seal.   To open just push the button again.   Everything stays fresh and sealed.  
The container is a hard plastic and has tiny feet on the bottom.  They are not non slip but I think they are used for stacking containers.