Glass Jacketed Beaker 250ml Double Layer Lab Reactor Vessel with Upper and Lower Hose ConnectionsA glass jacketed beaker is a laboratory vessel designed for chemical reactions that require precise temperature control. It consists of two layers of glass, with an inner layer for holding the sample or solution and an outer layer for insulation. The jacket between the layers allows for temperature control by circulating fluid through the jacket, and the upper and lower hose connections enable this fluid to flow in and out. The 250ml capacity