Borosil® Erlenmeyer Flasks have uniform wall thickness, perfect for evenly distributed heat. The classic conical shape promotes effective mixing. Beaded rims confer durability & crack resistance. Graduations & marking spot further improve the functionality of these essential lab tools.Available in from 10mL to 5L. The 10mL option does not have graduations. Flasks comply w/ ISO/DIN 1773, w/ the exception of the 10mL, 125mL, & 150mL options. In collaboration w/ Borosil Glass Works, Foxx Life Sciences is proud to bring the outstanding quality of Borosil® Type 3.3 Borosilicate glassware to North America for the first time. Manufactured from the same USP Type 1 borosilicate glass that North American scientists have come to trust, Borosil® Laboratory Glassware offers unparalleled mechanical strength, clarity, & reliability at competitive prices. & thanks to a unique annealing process, Borosil® Glassware is stress-free & incredibly resistant to thermal shock.