Adjustment function: Thickened quenching adjustment screw, clockwise adjustment force is large, counterclockwise adjustment force is small, easy to use, used with locking pins, adjustable size, improve work efficiency, and reduce employee fatigue. Selflocking design: Our spring balancer is specially designed for lifting, with builtin selflocking control system, precise control, high safety factor, special aviationgrade steel inside, precision manufacturing, flexible operation, can help you lift things easily, Save you more energy. Good helper at work: Equipped with a safety device, when the hanging object is overweight and the coil spring breaks, it can be locked immediately to prevent the hanging object from falling. Safety protection: The alloy steel hook is equipped with a safety buckle, which will not fall off during use. The spring balancer is attached with a rubber sleeve, which can protect the tool and the balancer from wear and tear, and double the safety. WITH SAFETY DEVICE: This product can be used to manually lock the suspended object with a safety device. If the suspended object is overweight and the spiral spring is broken, can be locked immediately to prevent the suspended object from falling