These JoyJolt 8pc Glass Nesting Kitchen Mixing Bowls with Lids are nice quality, very thick, heavy glass. The nesting bowl sizes are great for storing away leftovers without taking up too much space. They're a bit on the smaller size, but great for mixing up cakes or brownies, food prep, mixing up sauces and storing leftovers. I like that the box lets you know they're lead free. They're also dishwasher, microwave, and freezer safe. Three of the four lids fit too loosely to be airtight or leak proof. Overall, I like these bowls, and I think they are very handy in the kitchen.