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Colored Double Wall Glass Cups

The colored double-wall glass mug features two seamless walls of borosilicate glass that create an insulating layer, so coffee and tea stay piping hot and delicious while the cup is always cool to the touch. This drinking glass comes in various colors: blue, green, pink, grey, or customized to your favorite color.

Description

The colored double-wall glass mug features two seamless walls of borosilicate glass that create an insulating layer, so coffee and tea stay piping hot and delicious while the cup is always cool to the touch. This drinking glass comes in various colors: blue, green, pink, grey, or customized to your favorite color.

Borosilicate glass contains boron trioxide, which has a very low coefficient of thermal expansion. This means it will not break under extreme temperature changes like ordinary glass. Its durability makes it the glass of choice for high-end restaurants, laboratories and breweries.

Borosilicate glass is composed of about 15% boron trioxide, a magical ingredient that completely changes the behaviour of the glass and makes it resistant to thermal shock. This allows the glass to resist extreme temperature changes and is measured by the "coefficient of thermal expansion", which is the rate at which the glass expands when exposed to heat. This allows borosilicate glass to go straight from the refrigerator to the oven rack without breaking. For you, this means you can pour boiling hot water into borosilicate glass and not worry about the glass breaking or cracking if you want to make tea or coffee.