The glass jars for food storage are made of high-quality borosilicate glass, which is lighter and more heat resistant than ordinary glass jars, and can withstand temperatures from -20 degrees to 150 degrees. The thickened glass makes the canisters durable and sturdy. Thanks to that, the food storage canisters are able to put it in the fridge and microwave (remove the bamboo cover) or put it in the dishwasher to clean it.