Oxygen flask, Winkler, soda-lime glass 250-300 ml, with glass stopper NS 19/26 pack of 2

For the determination of oxygen dissolved in water. The measured volume is specified to two decimal places. White withe inscription field. Solid, obliquely cut NS glass stopper can be secured with a fastening clip. Each flask is calibrated with its own stopper. Stoppers and flasks are therefore not interchangeable. The bottle and stopper each have the same device number.