The heavy wall borosilicate filtering flask is a robust and reliable laboratory glassware item that excels in its construction, featuring a heavy-duty rim, bolt neck with upper tubulation, and durable white enamel graduations, all while meeting the strict standards set by ISO 1773 for narrow-necked boiling flasks. Crafted from 3.3 heavy-duty Borosilicate glass, this flask is prized for its exceptional thermal shock resistance and physical strength, making it a vital tool in laboratories. It seamlessly withstands rapid temperature fluctuations and offers steadfast protection against breakage, guaranteeing precision and durability for a wide range of scientific applications.