To replace the atomizer in the G Pen Roam, first flip the tank lid upwards to expose the quartz tank underneath. Be sure to allow the tank to cool completely before handling. Next gently pull the quartz tank with silicone cover away from the Roam's base - the tank itself can then slide downward and out of the tank cover. Insert the new Roam atomizer into the silicone tank cover, ensuring the tabs line up to fit flush. Finally, slide the tank and cover back into the appropriate slot on the Roam.