Eisco Labs Thistle Funnel Made of borosilicate glass Stout walled 11.75" Tall Does not include Clamp Eisco Labs 11.75" Thistle Funnel , Borosilicate glass, Stout walled - Does not include glass Eisco Labs Borosilicate glass has the following heat tolerances: Strain Point -515A°C | Annealing Point 565A°C | Softening Point 820A°C.