It is made from high-quality amber Boro 3.3 glass, providing excellent chemical resistance and thermal stability. This flask is Class A certified, ensuring high accuracy for precise liquid measurements. It features a NS 19/26 neck size, ensuring compatibility with a variety of laboratory glassware, and includes a PE stopper for secure sealing. The white scale offers easy visibility for 500 mL measurements, and batch certification ensures traceability for quality assurance. This pack of 2 is perfect for laboratories, research, and educational settings that require precise and reliable liquid handling for medium-volume applications.