This Pyrex® distilling apparatus is for determining water content in petroleum or bituminous products. It is graduated upwards from the stopcock to 3mL in 0.2mL divisions, and from 3mL to 20mL in 0.5mL divisions. With 24/40 Standard Taper inner and outer joints. For replacement stopcock plugs, see Cat.No. 1-7680. For replacement retaining clips, see Cat.No. 1-7280. Reference: Barrett method B-2. Also can be used as Dean Stark distillation apparatus specified in British Standard 756, but utilizes a common U.S. ground joint. It is also an optional setup for ASTM D-95.