Stonylab Dewar Flask, Cylindrical Form Borosilicate Glass Dewar Flask with Aluminum Base, 300mm Interior Depth and 75mm Interior Diameter for Laboratory, 1000ml. Cylindrical Form Borosilicate Glass Dewar Flask with Aluminum Base, 300mm Interior Depth and 75mm Interior Diameter for Laboratory, 1000ml. Could be used for liquid Nitrogen Made of double-walled Borosilicate glass, StonyLab Dewar Flask is furnished with aluminum base. Fully silvered and vacuum pumped. A cushioned plastic rim is added to the bottom for more protection StonyLab ensures high quality products.