Wean Green cubes are made of a durable glass with a silicone sealed lid. When I say durable, I mean that Nate has dropped them on the floor many times without so much as a crack. They can, however, really hurt your toe in a direct hit (not that I would know anything about that, Nathaniel!). They are bpa, pvc, phthalate and plasticizer free and you can freeze or heat the cubes as needed. Plus, they are just really cute - the orange ("carrots") is my favorite.
Even though Nate has outgrown baby food, I still use them often. They are great for saving small bits of leftovers and for taking snacks on the road. Just the other day I put our cut up grapes in one for a lunch outing. The leftover grapes still looked perfect the next day when I discovered I forgot to clean the remains of our lunch out of the diaper bag. No leaks, no surprise raisins. (I feel like that could be a diaper slogan, right?)