For your safety in handling hot solutions, we are offering high-performance beakers of borosilicate glass for long-term resistance to wear and chemical corrosion. This borosilicate glass is the same material used in Pyrex® and Kimax®. Scientific Beaker Mugs are available in 400 mL or two styles of large 600 mL. Our Erlenmeyer Mugs are cut down from Erlenmeyer flasks and resist tipping and spilling. The caffeine molecule is enameled in white on the side of the Caffeine Beaker Mug.