Made from fully tempered soda lime glass, the KeepCup Brew Cork Edition features a natural cork band. Made in Portugal using waste product from the wine cork manufacture, the band is beautiful to hold. 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. For best results hand wash only. Lid off can be heated to 100°C/ 212°F degrees. Made from toughened soda lime glass – not unbreakable, but surprisingly durable