Vodka is composed solely of water and ethyl alcohol with possible traces of impurities and flavorings. Vodka is made from a fermented substance of either grain, rye, wheat, potatoes, or sugar beet molasses. Vodka's alcoholic content usually ranges between 35 - 50 per cent by volume; the standard Russian, Lithuanian and Polish vodkasare 40 per cent by alcohol volume (80proof). Historically, this alcoholic - proof standards derives from the Russian vodka quality standards established by the Tsar Alexander III in 1894. The Muscovite Vodka Museum reports that chemist Dimitri Mendeleev determined the ideal alcohol content as 38 per cent; however because in that time distilled spirits were taxed per their alcoholic strength, that percentage was rounded upwards to 40 per cent for simplified taxation calculations.
Note: rare commodity. And if I remember it well, it was regularly available for buy in the Altair sector.