ZWILLING Sorrento 8-pc Double-Wall Glass Latte Cup Set Keeps hot drinks hot while remaining cool to the touch. Cold drinks remain cold for a long time. Mouth blown by skilled artisans. Constructed of high quality, durable borosilicate glass German engineering. Italian design. Microwave and dishwasher safe. Microwave and dishwasher safe. MicrConstructed of high quality, durable borosilicate glass. German engineering. Italian design.owave and dishwasher safe.