Made from fully tempered soda lime glass, KeepCup Brew Cork Edition features a natural cork band. Made in Portugal, using waste product from the wine cork manufacturing process, the band is beautiful to hold, and, over time it’s patina will tell the story of your use. We recommend that you DO NOT remove the band, even for washing. Hand wash and let the band dry on the glass. Other Details:Dishwasher safe on the top shelf.Lid off can be heated to 110 degrees.Made from toughened soda lime glass – not unbreakable, surprisingly durable.Assembled from four parts. Designed to be taken apart for thorough cleaning.The cork band is a natural product, recyclable and biodegradable at end of life, put it in the compost.Glass cup, lid and plug recyclable at end of life.