Flask Boiling - Florence, flat bottom, wide neck with beaded rim 1000ml, borosilicate glass-EIS-CH0411E offers a thoughtfully designed, durable resource for hands-on learning. Made of high quality, heavy duty Borosilicate glass 1000ml capacity. Wide neck, flat bottom, beaded rim. 7.5" tall, 5.25" bottom diameter 3" neck length, 1.75" neck diameter Perfect for any science or home laboratory 1000ml capacity Florence boiling flask made out of high quality, heavy duty borosilicate glass. Wide neck, beaded rim and flat bottom. No stopper included. Flask measures 7.5" tall. Eisco Labs Borosilicate glass has the following heat tolerances: Strain Point -515°C | Annealing Point 565°C | Softening Point 820°C.