Flask Conical 250ml, narrow neck, borosilicate glass-EIS-CH0424F offers a thoughtfully designed, durable resource for hands-on learning. High Quality Borosilicate glass 250ml with 50ml graduations (1) Single Flask 5.75" tall, 3.25" base diameter 1 Single Erlenmeyer conical Flask 250ml, narrow neck, Made from high quality borosilicate glass. 250ml with 50ml white graduations Height: 5.75" | Base Diameter: 3.25" | Neck Inner & Outer Diameters: 28mm, 34mm Autoclavable, with superior chemical durability. Low temperature gradient- can withstand high temperatures & thermal shocks. Eisco Labs Borosilicate glass has the following heat tolerances: Strain Point -515°C | Annealing Point 565°C | Softening Point 820°C. Eisco Labs proudly manufactures its own products using state-of-the-art equipment, and following the highest standards of quality control. Each product is carefully designed by a team of laboratory professionals and experienced engineers with quality and durability in mind. They are manufactured with only the highest grade, raw materials and according to international quality standards to ensure that they can withstand use in even the toughest laboratory environments.