Rawal 5000ml Borosilicate Glass Round Bottom Boiling Flask The Rawal 5000ml Round Bottom Boiling Flask is made from high-quality borosilicate glass, offering excellent chemical resistance and durability. Its clear and transparent design allows easy observation of contents, making it ideal for chemical reactions, boiling, and heating in laboratory settings. This traditional flask is a staple on laboratory shelves due to its resistance to thermal shock, ensuring safe use under high temperatures. The round bottom design ensures uniform heating, making it perfect for use with heating mantles or burners.