Our new Presso collection is made from silicone and borosilicate glass and can resist extremely high temperatures. The jar itself, except the lid, is microwave safe. The Presso collection invites the consumer to have full flexibility of storing any kind of products-all from very hot liquids to liquids with a high acidy level-without discoloration. The collection is designed to harmonize with any other product in Bodum's universe. To express Bodum’s environment friendly approach to design, Presso is made of fully recyclable materials. The environment friendly spirit has always been the company’s driving force - a part of Bodum’s principles where the form follows the function, and where good design should be affordable. This set includes three 34-oz. Presso Storage Jars.