12-HD980 Heavy Duty Steel Mullion Designed for double door applications from 8–10 feet, the HD980 Heavy Duty Steel Mullion is fire-rated and offers maximum strength and reliability when used with the 8800 Series Rim Exit Device. Downloads Catalogs Instruction Manuals Promotional Sheets Product Templates Parts Manual Interested in this product? Contact Us Related products EL980 Electrified Keyed Removable Mullion 988 Surface Bolt Kit L980 & L980A Keyed Removable Mullions