Merit Blue King Box is a pack of Merit Ultra Light cigarettes in the blue box packaging, king size. Merit is an American cigarette brand owned and manufactured by Philip Morris USA, first introduced in January 1976 as a low-tar alternative cigarette. The blue pack designation indicates the Ultra Light variety, available in king size box format.

Merit cigarettes are made with a blend of tobacco and flavoring ingredients including tobacco, water, sugars, propylene glycol, glycerol, licorice extract, diammonium phosphate, ammonium hydroxide, cocoa and cocoa products, carob bean and extract, and natural and artificial flavors. Merit Blue (Ultra Light) is sold primarily in the United States and select international markets.