This set consists of two borosilicate double walled espresso mugs each. This material is insensitive to temperature fluctuations and is therefore ideal for both hot and cold drinks and is light yet strong. Each glass has perfect functionality, keeping hot drinks hot and cold items cold. 
Features and Benefits:

• 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