Bell Jars: Vacuum & Non-Vacuum Types, PYREX®
PYREX® round glass vacuum bell jars are manufactured from a specially blown, sturdy glass material and features a fine ground finish at the open end. Pyrex glass bell jars are available both with and without a bottom rim flange. The flat ground bearing surface has a contact area equal to the wall thickness at the open end of the jar. Warning: Do not use flangeless style bell jars with vacuum applications. Do not use any style PYREX bell jars with heat or pressure. Reusable. Material: Corning Borosilicate Glass Code 7740.