It's thick plastic glass feel to it. The lids go on easy to click shut. The sizes are small more so for a lunch box/tote to eliminate plastic Tupperware. It is oven microwave n dishwasher safe. The largest rectangle looks like it can hold 2-3 slices of pizza or one slice of deep dish. The largest circle can hold a salad or fruit salad but not a whole bag of grapes. And the largest square is mashed potatoes leftovers. Hope that helps. Each size stack nicely into the other but only one lid snaps on and it's for the largest container. Pic of example.

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I bought this set about a month ago mainly to have a variety of sizes to to be able to take with me to work. I also use these for food storage/prep. I’ve waited this long to write a review in order to fully give everything a good try. These containers ARE leakproof! When I put them in my lunch bag I have to put them in sideways and when I get to work there’s no food leakage. Heating food in them is no problem and they are very pretty as well. The different sizes really help because you can put many in the fridge without taking up too much real estate lol. Also, these are strong. Everyday I do the same thing: heat my food up, clip the sides shut and carry it to my desk. I LOVE my new Bayco set and highly recommend it! If you’re ready to ditch the plastic, this set is fantastic!

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I just moved into my new apartment and I needed tubberware I wanted glass instead of plastic. These are perfect size for small left overs each shape comes with three sizes, small medium and large. The shapes include square, circle and rectangle each container comes with its own lid. My only complaints would be they could be a little bigger and more colors like pink. Other than that I’ve been able to store a little bit of everything on mines. I’ve even put fresh strawberries in one.

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As lots of people are doing these days, I'm also minimizing the use of plastic. I also purchased an Instant Pot for meal planning. Awesome combo here!