KitCDS

The kit for the production of chlorine dioxide consists of:

Glass jar with hermetic closure.
Beaker for reaction. The beaker is of adequate height so that water does not enter its interior during the reaction.
5ml syringe with which you can measure sodium chlorite and activating acid.
3 strips to measure the concentration of Chlorine dioxide after the reaction has finished and the chlorine dioxide has dissolved in the water.
140 ml of sodium chlorite.
140 ml of hydrochloric acid activator.

You can see how to prepare it HERE.
Act with great caution and always in a place with good natural ventilation.