KGW-ISOTHERM manufactures about 400 different types of reaction vessels made of glass in series. The reaction vessels are produced with a volume from 250 ml up to 20 litres with flat bottom, round bottom or bumped boiler end. As closing the flange system by SCHOTT with O-ring grooves is used. The bottom-outlet is available as standard with two different valves, the laboratory valve "L" (spindle is pressed while turning, type Torion) and the industrial valve "J" (spindle is springloaded and regulates herself), and the spherical ground joint S40. Every valve in the reaction vessels is dead volume free.