United Scientific? Fg5340-2000 Laboratory Grade Borosilicate Glass Heavy Wall Heavy wall borosilicate filtering flask includes a heavy-duty rim and a bolt neck with tubulation. Graduations are printed in durable white enamel. Manufactured from low-expansion Type 1, Class A Borosilicate 3.3 glass that complies with ASTM E438 Standard Specification for Glasses in Laboratory Apparatus. It is low alkali glass with a typical chemical composition of approximately 81% silica, 13% boric oxide, 4% sodium oxide, and 2% aluminum oxide. It is virtually free of magnesia-lime-zinc group, and contains only traces of heavy metals. Capacity: 2000mL (2L). Tubing Size: 1/2". Recommended Stopper Size: 9.5 Graduation Range: 600-2000mL. Graduation Interval: 200mL Made from industrial quality Borosilicate 3.3 glass, these flasks are built to withstand high temperatures and thermal shock. These flasks feature dual scale graduations per ASTM-E960 standards. All United Scientific flasks are dishwasher safe. Every United Scientific flask is manufactured using state of the art equipment. Every product undergoes various rounds of quality control, and is designed to ensure a smooth, consistent experience for our customers. Dimensions (OD X H): 170 x 305mm