This 50mL narrow-neck Erlenmeyer flask is made from borosilicate glass and comes fitted with a standard size #7 bark cork stopper (15-21mm diameter, 25mm length). The flask features approximate graduations and a flat bottom for stability, making it suitable for holding liquid or solid materials. The borosilicate glass construction provides superior chemical durability and thermal shock resistance. The flask is autoclavable and can withstand high temperatures, with heat tolerances including a strain point of 515 °C, annealing point of 565 °C, and softening point of 820 °C. This flask is a practical choice for general laboratory use, classroom experiments, and household applications.