Borosilicate glass Liebig condenser Non-jointed EISCO Liebig Condenser, 500mm Jacket, 700mm total length (1) Liebig Condenser These borosilicate glass Liebig condensers are of high quality and have narrow jackets for efficient cooling. Eisco Labs Borosilicate glass has the following heat tolerances: Strain Point -515°C | Annealing Point 565°C | Softening Point 820°C.