Bath Crystals Cold Season Eucalyptus. Made with valuable essential oil of eucalyptus oil provide a pleasant, refreshing aroma to stimulate the mind. Eucalyptus oils are obtained from the fresh leaves of Eucalyptus leaves, which has a long history is use against colds. Working as a natural disinfectant is the perfect choice during allergy and cold and flu season, in a perfect travel size sachet containing enough for one bath.