Mercury Seal - 6.79 Feet - 8177121. The Mercury Seal 6.79 Feet (8177121) is an OEM-quality trim seal designed to provide a watertight barrier between your engine components and external elements. Engineered for long-lasting performance, this genuine Mercury part is essential for keeping moisture, debris, and corrosion at bay in marine environments.. Key Features. Precision-Cut OEM Seal - Measures 6.79 feet for accurate fitment and easy installation. Durable Marine-Grade Material - Built to resis