The beakers are hard plastic that is easy to clean. They stack inside of each other and the rubber bottoms means I have never had one slip around on the countertop no matter how messy or wet I might get things from cooking and baking. Below you can see how they lay out in a 'rainbow" pattern, too, which makes this a colorful gift that might also make a social or political statement. Yes, I know this isn't scientifically a rainbow, the blues aren't quite right.
Orange = 3/4 cup, 6 oz, 175 ml
Yellow = 1/2 cup, 4 oz, 125 ml
Green = 2 oz, 4 Tbsp, 60 ml
Aqua = 1 oz, 2 Tbsp, 30 ml
Blue = 1 Tbsp, 3 tsp, 15 ml
Purple = 1 tsp w/ quarter marks, 5 ml
Again if you'd like to buy a set of these delightful beakers and help support The Chocolate Cult, you can follow the link below and buy your own. They also make great gifts!