These 1L Class A PYREX® volumetric flasks have machine-blown bodies to which are sealed heavy-beaded, heavy-tubing necks, tooled for No. 1000 polyethylene snap-caps. The graduation line is sharp and permanent. Large white block letters make the inscription easy to read. These Class A volumetric flasks have been manufactured to Class A tolerances as established by ASTM E-694 for volumetric ware, ASTM E-542 for calibration of volumetric ware and ASTM E-288 for volumetric flasks. Material: Borosilicate Glass Code 7740. Capacity: 1000mL. Flask Style: Volumetric. Flask Shape: Flat Bottom. Top Style: Heavy Duty Rim. Neck Style: Long. Stopper: No stopper. Accuracy Class: Class A. Cap Style: Snap Cap. Cap Material: HDPE. Cap Color: Blue. Snap Cap No: 1000. Height (approx): 310mm. Outer Diameter (approx): 125mm. Corning® #: 5580-1L.