This PYREX® boiling flask has a full length outer 24/40 standard taper joint at the top. Wall thickness is carefully controlled to provide the proper balance between thermal expansion and mechanical strength for greater shock resistance. Excellent chemical durability results in contamination-free results and long life under the toughest lab conditions. Normal working temperature for this PYREX® boiling flask is 230°C. Adapters are available to connect flasks with different size joints, thus allowing numerous combinations for diverse assemblies (sold separately). Non-Sterile. Reusable. Material: Borosilicate Glass Code 7740. Capacity: 200mL. Flask Style: Boiling. Flask Shape: Pear Shaped. Top Style: Standard Taper Joint. Neck Style: Short. Stopper Style: No Stopper. Standard Taper Joint: 24/40. Height: 140mm. Outer Diameter: 76mm. Corning® #: 4318-200.