"Dr. Oxygen" is a portable oxygen generator, most efficient, economical and safe. "Dr. Oxygen" generates more than 10 liters of 99.8% oxygen by one time simple mixture of a couple of special powder packs and water into the portable reaction tub. There is no need using electric power or highly pressurized oxygen, because "Dr. Oxygen" works on the basis of a safe chemical reaction; that is, 'Powder B(90g)' contains oxygen and 'Powder A(5g)' controls the duration and degree of reaction as a stabilizer. The US patent (No. 043487) and our quality control warrant this stabilizer and the special way of safe chemical reaction.