Retractable Spring Balancer 6.6-11LB Tool Fixtures Holder Hanging for Assembly-line Retractable 3-5kg Range Spring Balancer Suitable for Assembly-line, people working side by side, tools, fixtures and parts, raw materials, suspension and alignment, manipulate electric, pneumatic and hydraulic apparatus,etc To enhance work efficiency and reduce fatigue Remained stable tool position, correct work No need power or gas source, Easy and quick to install