Please see the picture below. Nothing propped it open.

I bought 3 sets of these . They are very durable and the lids do not stain.

Half of the lids broke in the first month.

The perfect size for leftovers of various portions and pack down very efficiently. Will probably buy only these for the rest of my life.

I put a cold container from the refrigerator to the microwave and it exploded! Never had this for my other containers.

These are perfect for meal prep. All the shapes and sizes are perfect for the various foods that I prep. Great for environment♻️ no more plastic.

This glass container are excellent. I use them for meal prep. My favorite part is the spill proof lids.

The different size containers are very nice, the lids are terrible, hard to close and hard to open. Would not recommend them .

Several of the lids are hard to close. Slam against the counter hard to close. The seals are a little difficult to remove without damaging them.

It says microwave safe, but beware. One of these just exploded in my microwave in less than a minute!