[Source] Antiox breath masks were used by Kel Dor to survive in space and oxygen atmospheres. The breath mask provided the mixture of unique gases found on Dorin's atmosphere (Dorin gas and helium), while reducing the oxygen level to one which was tolerable by Kel Dor physiology. It also protected the wearer's eyes from the harmful effects of oxygen to Kel Dor. The masks may also have been used to hide identity.