Patent No. 9,038,360Recessed head to eliminate snag pointsInstalls in seconds with a flat head screw driverCost effective and more secure compared to attachment methodsUnique pin design to prevent backing out due to vibrationNo thread fastener requiredMeets ANSI/ISEA 121-2018 Features Max Tool Weight: 15 lb Max Tether Length: 60" Commonly used with: Hammer|Combo Wrench Opening Size: 1.15" x 1.15" Quantity: Single Simple installation - does not require tape or heat gun Exclusive, patented design (Patent Number 9,038,360) Compliance This product meets the following regional compliance standards ANSI/ISEA 121-2018 Industries This product is often used in the following industries Construction Utility General Industry Downloads Test Report Declaration of Conformity Instruction Manual From The ESS Team According to the product listing, the SHKL1212LK is an anti-vibration tool tether shackle [1]. It is used to secure tools to a tether, preventing them from falling and causing injuries [1]. Here are some of the reasons to use it: Prevents injuries: By securing tools to a tether, the SHKL1212LK prevents them from falling and potentially injuring workers or bystanders [1]. Easy to install: The SHKL1212LK is easy to install, making it a quick and convenient way to secure tools [1]. More secure than other attachment methods: The SHKL1212LK is a more secure way to attach tools to tethers than other methods, such as knots or carabineers [1]. Meets ANSI/ISEA 121-2018 standards: The SHKL1212LK meets ANSI/ISEA 121-2018 standards for fall protection [1]. This means that it has been tested and certified to meet specific safety requirements.