I looked at the box in the basement, I use Bernardin 250ml jars. They come in boxes of 12. I have been making all kinds of soups and I regularly make a batch of Chili which I freeze in these jars. I have been doing this for about 5 years and never had one break. I put the food into them hot, put them in the fridge over night and freeze them the next day. It is so convenient because both my DH and I can just pick one out the night before and take it in our lunch when we don't know what to make or just run out of time!