They're made directly for Home Science Tools with highquality borosilicate glass that can be heated directly in an open flameGlass Beaker 10,000ml Heavy Borosilicate Glass 10 Liter Griffin Low Form style beaker made from heavy borosilicate (heat resistant) glass No graduations or marking area on glass Capacity 10,000 mL / 10 L Graduations Ungraduated Height 1386 Inch (352mm) Top Inner Diameter 6 Inch (225mm) Bottom Diameter 787 Inch (0mm) WeightGlass PYREX® Beakers (Corning 1000) Griffin low form, double scale graduated beaker, with spout, manufactured with uniform wall thickness, offers optimum balance between thermal shock resistance and mechanical strength For convenience, the 250 through 00 mL beakers have a double graduated metric scale to indicate approximate content 1000 ml glass beaker price