The A.T.O.M. Exosuit (Advanced Technology Operating Mechanism), officially designated O.M.A.C. by Queen Consolidated, was an exosuit designed by Ray Palmer. It was used by Ray in his exploits as a vigilante around Starling City as The Atom. Components of the suit were made out of dwarf star alloy, a rare substance that Ray had acquired during his final year as the CEO of Palmer Technologies.
Ray Palmer had virtual blueprints for the A.T.O.M. Exosuit, which he holographically projected and observed. He later showed Felicity Smoak the blueprints after she suspected something was up, and he revealed to her his plans, asking that she help him. After spending over a week with little rest and food, Ray Palmer had completed the exosuit and gave it a test through Starling City.
After Ra's al Ghul had the League of Assassins begin impersonating The Arrow, Ray made it his mission to bring him to justice. He used the suit at the scene of a crime that the Arrow had seemingly committed, with eight dead bodies surrounding him. He used the x-ray and facial recognition software built in to the suit to identify him as Oliver Queen. They later fought, with Ray easily overpowering the Arrow. However, he realized the suit's power source was located in the leg and so threw a flechette at it, reducing Ray to his knees, before he assured of their being on the same side.
Ray, along with Felicity, traveled to Central City to seek advice from Barry Allen's team, especially hoping for Cisco Ramon's help on fixing and improving the previously damaged power source. He later used the suit to save Tina McGee from Brie Larvan's swarm of robotic bees. With Cisco's giving him advice from the S.T.A.R. Labs truck, Ray lured the bees into a nearby lake, where the water fried their electronics, at the cost of frying his suit as well. With his jets malfunctioning, Ray managed to land inside the truck. He and Cisco then fist-pumped, the latter soon regretting it due Ray's glove being metallic. Afterwards, Ray confiscated one of the robotic bees, getting the idea to make the power source for his suit smaller.
After The Arrow was seemingly locked up in prison, Oliver Queen was forced to go to Ray for help to take on a meta-human, Jake Simmons. Ray tried to incapacitate him, but the plasma shots fired from his suit were simply absorbed by the man. Allowing Oliver to help, he controlled the suit remotely, using simple hand-to-hand combat to try and knock him out. However, Simmons used a shock of plasma to damage the suit and cut the link between them, meaning that Ray had to take over from Oliver. In the end, he beat him and flew him to Central City, to be locked in S.T.A.R. Labs' particle accelerator prison.
Sometime later, trying to prevent Ra's al Ghul and Oliver from destroying Starling City via bioweapon, Ray accompanied a team to Nanda Parbat. Though they couldn't stop the plane in time, their plan B, Ray, flew straight through it, seemingly stopping the attack. However, Ra's had kept the vial from the plane.
Finally returning home, Ray began to work on fixing his suit, hoping to spread a vaccine to the Alpha-Omega virus across Starling. However, as Oliver was in trouble, Ray stayed at Palmer Technologies while Felicity donned the exosuit, only just knowing how to fly. After the defeat of Ra's al Ghul, Ray attempted to test the suit's possible shrinking abilities. However, something went horribly wrong, and the suit generated an explosion, destroying several top floors of Palmer Technologies, though both it and Ray where unharmed and shrunken down.He remained trapped like this for several months and became Damien Darhk's prisoner. Darhk desired the suit for his own plans but couldn't use it while it was small. Ray managed to contact Felicity, revealing that he was alive, and provided her with a list of items to create a device that would restore him to full size. With Curtis Holt's aid, the device was created and Team Arrow rescued and restored Ray and the suit.
Ray avoided revealing his re-appearance, staying "dead" in the eyes of the public. At some point, he was recruited by Rip Hunter to become a part of his time-traveling team, bent on saving the world of 2166 from the tyrannical rule of Vandal Savage. After Ray left 2016, his brother Sydney Palmer has acquired the A.T.O.M. technology, claiming it as his own. Ray speculated that Sydney sold his research to the military, while his descendant Dr. Brice claimed that Sydney was the one to create the company that would produce a line of autonomous robotic versions of the exosuit for the Kasnia Conglomerate.
In 2166, Ray enlisted Jackson's help in order to utilize the power of the Waverider's time drive to reverse the polarity of the suit's dwarf star matrix, thus also reversing its primary function, where instead of shrinking him, he was able to temporarily increase in size exponentially to fight the Leviathan.
After getting stranded in feudal Japan while attempting to rescue Nate Heywood who had been sucked out of the Waverider's open door, Ray is knocked unconscious and held captive by the Shogun, Tokugawa Iemitsu, and his men. Tokugawa claims the suit for himself, despite Ray's bluff that the suit could kill him as it was designed for his body type. Ray is rescued by Mick Rory, Sara Lance and Amaya Jiwe as Tokugawa attacked them while wearing the suit. The Legends conclude that the only way to stop Tokugawa is to help Nate learn to "Steel on" as he was the only member impervious to the suit's weaponry but later told Nate the plan was to destroy the suit with Tokugawa still wearing it and ranted about how he had to destroy something that took weeks to create and that made him a hero. During a fight between Ray, Masako, the now-Steeled version of Nate and Tokugawa, Nate managed to explode the suit while Tokugawa was busy preparing to attack Masako, killing Tokugawa in the process. 
- Flight: The suit contains high powered propulsion jets on the back, shoulders, upper arms, and in the legs, allowing the wearer to fly with great speed. The wearer can also perform aerodynamic feats with ease, as well as simply hover.
- Enhanced durability: The suit can resist several forms of damage, such as bullets or arrows. It can be caught in explosions and not have a scratch on it, such as when he faced off against a jet. getting hit with a missile and being able to stand back up after crash landing. Ray was also shot down from thousands of stories up and fell to the ground without being harmed due to his suit. However, the facemask appears to be a weak point, as Deathbolt was able to crack it, and injure Ray's face. The other weak point is the main power source on the left hip of the suit, as it an be easily damaged and destroyed with a simple blade, causing the suit to lose all power and almost trap the user under the weight of the suit without the internal mechanisms holding it for the user. This can leave the user defenseless to attack.
- Enhanced strength: The A.T.O.M. can somewhat increase its user's strength. When in motion, especially when it land hard after flight, it exerts great physical force, as much as a bullet, allowing it to give great damage to something as strong as concrete, easily creating large craters in concrete grounding when landing on it too hard. Its metallic composition can allow the physical force it generates to be as much as an object as hard as stone or metal, meaning a strike from the suit equals a strike from a metal or stone object with human strength or similar strength. The mechanism in the suit allow a wearer to exert great strength and force with inhuman ease. Ray was able to hurl Deathbolt across a room and into a wall, leaving a dent. He is capable of knocking meta-humans out with a single punch. When Felicity wore the suit, she was strong enough to catch and lift Oliver while flying with enough momentum. Strength is unaffected by the suit's shrinking, allowing Ray to physically overpower multiple opponents while shrunken and in flight. While small, Ray even used his flight to pierce clean through one of The Hunters like a bullet. Ray has even shown that he can use the energy weapons on his forearms while he is punching an opponent to further enhance his attacks. However, Vandal Savage managed to overpower Ray while he wore this suit, using his own momentum against him.
- Compressed hard light/Photon blast: The suit's primary offensive function is a direct energy weapon on each forearm that creates blasts of focused blue energy that generate similar force to that of powerful windstorms. The weapon and its computerized targeting system are both manually activated by the wearer. These blasts are powerful enough to crack stone, dent metal and physically repel a target, while they also are capable of knocking a target unconscious, and causes an explosion on the The suit builds up charge on the right arm to fire the weapon's charge, meaning that it is not exactly instantaneous. With some upgrades, the suit can fire its energy noticeably faster and can recharge far faster than originally. Only the size of the blasts, not their capabilities or power, are reduced by the suit's shrinking. As seen in a fight with Vandal Savage's men, the blasters can be knocked off if hit hard enough. In Midnight City, Felicity said that the suit fired lasers, while Ray corrected her and said it fired compressed hard light. Ray called the weapons "compressed light beams", correcting Jefferson Jackson when the later called them "laser blasters" during his fight with The Leviathan. However, later on, he called his weapons photon cannons, as he did in Blood Ties when he volunteered to destroy the knife fragments inside Kendra, saying "I can shrink down, slip into her bloodstream, and use the photon canons to vaporize the knife fragments." In addition, it is revealed in Marooned that the blasts can reduced and condensed into blowtorch or laser like welding beam, which he used to repair damage on the exterior of The Waverider. In Left Behind, Ray punched Chronos while firing a blast, combining his strength and energy weapons to enhance his attacks further.
- Electricity projection: The suit is equipped with gloves that project arcs of high voltage electricity via the fingertips. The electricity is capable of sending a target backwards and is not lethal, though it may be able to harness higher voltage for lethal attacks. In addition, this weapon can fire in a millisecond whereas the primary solid light weapon takes a few seconds or less to charge up and build energy to fire, making the electric weapon slightly faster in functionality than the primary weapon.
- High-spectrum portable radiograph: The suit has an in-built high-spectrum radiograph, essentially allowing Ray x-ray vision through objects or scan objects at all angles, even the most obscure or microscopic.
- Advanced computer system: The suit's computer systems are capable of scanning objects and identifying in seconds, even if the object is obscured. These systems can create a near three dimensional image of whatever it sees and can uses to this to render a scanned object and other information surrounding it within its advanced heads-up-display (HUD). The HUD is capable of processing several images at once. It also has a targeting system and projects targeting reticles on the HUD. The suits targeting systems are in since with its weapons and can activate and use a selected weapon milliseconds after selecting a target.
- Advanced facial recognition software: Felicity Smoak built the suit to make use of facial recognition, regardless of how vague or hidden it is, meaning it is capable of scanning any target and making a nearly instantaneous match to the subject.
- Neural link: A new addition to Ray's suit allows anyone wearing a special headset to control the A.T.O.M. suit. This can be used by Palmer in the A.T.O.M. suit, for ease of use, or from an external source to control the suit from afar.
- Shrinking: By utilizing similar nanites to those used to shrink Palmer's blood clot in his brain, the suit is able to shrink the space between atoms, even keeping the subject shrunken down after removing the suit. This ability does not effect strength or the suit's hard light blasts. In addition it can be made portable by shrinking it, leaving it with the appearance with a small figurine that can be carried around in Ray's pocket until he makes it enlarge and causes it to automatically open for him to put on and use.
- Space survival: The A.T.O.M. suit contains an oxygen supply to allow the wearer to survive in the vacuum of space. The faceplate also extends completely over the face to keep the oxygen contained.
- Growing: By properly charging the A.T.O.M Suit with enough advanced energy, such as from the The Waverider's auxiliary time drive, it can reverse the polarity of the dwarf star matrix, allowing the wearer to grow to gigantic sizes while proportionately increasing their strength as well. The weaponry of the suit also remains intact and usable, likewise become much stronger.
- Size changing beam: It is revealed in Legendary that Ray has designed a red energy beam on his arm that can shrink a Nth metal meteorite primed to detonate and reduce its subsequent explosion to a tiny and harmless burst.
DC's Legends of Tomorrow
Behind the scenes
- In the DC comics, Ray Palmer goes by the superhero alter ego The Atom, and has a suit that allows him to shrink to a molecular level.
- In the DC comics, O.M.A.C. (which initially stands for "Observational Meta-human Activity Construct", and then later "Omni Mind And Community") are powerful cyborgs associated with Brother Eye. In an earlier incarnation, he was a creation of Jack Kirby known as the "One Man Army Corps", an individual infused with power by Brother Eye.
- The A.T.O.M Exosuit was originally set to first appear in the arrow episode, ""; however, due to production of the suit not being ready, the date had to be pushed back to episode 15, "".
- The energy weapons on the suit have been called both "Photon Blasts" and "Compressed Hard Light Beams".
- Although a direct correlation was not made, when Rip Hunter's team visited Star City in 2046, they witnessed Oliver Queen wielding an detachable, artificial left arm similar to that of the A.T.O.M. suit's, after his own was cut off by Grant Wilson. It is unknown how Oliver obtained it, while it is shown that Oliver seems to not use it as much, as he left it discarded in the derelict Arrowcave until the episode's end.