The Equilibrium tube demonstrates that liquids will maintain the same level, despite their shape 4 different tube shapes - large straight tube, squiggly tube, tube with two bulbs and narrow straight tube Includes sturdy, detachable base Stands 10" tall Great for classroom demonstration Equilibrium tube apparatus, featuring 4 tubes in different shapes. Made of high quality, borosilicate glass. Great for classroom demonstration illustrating that liquids will maintain the same level - regardless of shape. Mounted on plastic base 10" height. Base diameter measures 4". Glass tubes measure 6.5" wide. Eisco Labs Borosilicate glass has the following heat tolerances: Strain Point -515°C | Annealing Point 565°C | Softening Point 820°C.