Robes of Atom ' s Devoted The Robes of Atom ' s Devoted is a piece of clothing that can be obtained in the " Fallout 4 " add - on " Far Harbor " . Characteristics . The Robes of Atom ' s Devoted is a piece of clothing that appears visually similar to other variants worn by the Children of Atom . It cannot be worn with other armor pieces ( excepting helmets ) , but it can be upgraded with ballistic weave . While the base effects include an extra + 5 Radiation Resistance over standard Children of Atom rags , an unmarked effect is this resistance value increases as the wearer becomes more irradiated , eventually maxing at greater than 2500 rad resistance , making the wearer practically immune to environmental radiation at the expense of having an extremely low health pool . However , this effect changes once the wearer becomes even more irradiated , which can be accomplished by consuming items that irradiate the user such as irradiated blood or durable sludgepak . Once the player character has surpassed this radiation value , almost filling the entire health bar with red , the effects shown in the Pip - Boy do not change but the player character becomes completely immune to radiation and health can be restored as normal back to maximum HP . Consuming irradiated items will cause no ill effect from radiation ( despite still showing rad numbers upon consumption ) and Geiger counter clicks and rad number display from environmental radiation will no longer occur . However , the health bar is almost entirely red and is no longer an indication of current HP , so this must be checked in the Pip - Boy . Once immune to radiation , the clothing must be worn at all times and the player character ' s radiation level must not be lowered to maintain the effect . RadAway , Solar Powered rank 2 during the day , etc . can remove the unique clothing effect by causing the player character ' s radiation level to drop below the threshold value . Once the effect is removed , the player character ' s HP immediately drops according to standard radiation effects . Wearing power armor initially appears to work , but as power armor replaces all clothing bonuses the effect is removed and actual HP follows standard radiation rules despite the Pip - Boy and heads - up display . Leaving the power armor or re - equipping the robes after removing them will reintroduce its special effect as long as the player character ' s radiation level is past the trigger threshold , but any health lost will need to be healed . Due to this robe ' s unique undocumented effect once upgraded with ballistic weave to protect from creature encounters it can become a viable armor for traversing the Glowing Sea , as the environmental radiation in even the most irradiated zones becomes harmless to the player character and HP can be maintained at the maximum amount if the unique effect is active . It ' s also worth noting that while the unique effect of maintaining maximum health and rad immunity is active , you can still make use of other unique effects like Inquisitor ' s cowl , Inquisitor of Atom and also rad affected legendary effects like " rad powered " and maintain their maximum bonuses . ( + 4 intelligence , + 100 % extra damage and + 7 strength respectively )