Roy Mustang’s custom made gloves are the main ‘weapons’ he uses. He created them with pyrotex/ignition cloth, a cloth that when rubbed together, create a spark. He has a unique Transmutation Circle for flame alchemy on gloves that allow him to manipulate the oxygen in the air.
When facing a target, Mustang raises the oxygen density around the them at which point it creates a pathway between the two. He can then use the gloves to create a spark and attack the target. He uses his hands differently in battles. His right hand is mostly used for large explosives while his left hand is used for more accurate and smaller attacks.