Mario Bros. is a Multi Screen Game & Watch video game that stars Mario and Luigi. The Multi Screen unit is held sideways in a similar fashion to reading a book. The game was released in 1983 by Nintendo, and while named after Mario Bros. in the arcades, the game is not based off of it. Nintendo manufactured 1,000,000 units of the game worldwide. The game's model number is MW-56. The M stands for Mario, though it's unclear what the W stands for. Within the game's box was the game unit, two LR44 batteries, and instruction booklet and battery stickers.