3M™ DBI-SALA® Nano-Lok™ Arc flash twin-leg quick connect self retracting lifeline. Nano-Lok™ is ergonomically designed for ease-of-use and is ideal for direct connection to most harnesses. The extremely compact and lightweight design is virtually unnoticeable on your back, staying out of the worker's way and making it ideal as a lanyard replacement. Whether your application requires single or twin leg configurations, mounting to an overhead anchor or for connection directly to harness, there are dozens of models to choose from to suit almost any application. Nano-Lok™ locks quickly stopping a fall within inches providing more protection at low heights. In addition, tension is always kept on the lifeline, which reduces dragging, snapping and trip falls. Both features are key safety improvements.