National Hardware's 3/8" Quick Link is designed for fast, easy connections between two lengths of chain or for attaching accessories to chain. Steel body construction provides maximum durability. Installs quickly using a hex shaped bolt that easily opens and closes with an adjustable wrench. Quick Links are designed to make permanent and temporary connections. Quick Links should be used with chain or other items with equal or lower working load limits. Heavy Duty Rating with 2,640 lbs. Safe Working Load, always follow safe working load (SWL) limits included on packaging. National Hardware's Lifespan Limited Lifetime Warranty.