A traction winch for a cable or the like includes a winch frame, at least two sheave assemblies each having at least a first sheave and a second sheave, each sheave having a single circumferential friction surface for the cable. The lens includes two or more portions having different patterns to generate different light beams when the laser instrument generates the light through either of the portions of the lens, by moving the plate relative to the housing. An attracting magnet is placed outside the cap. A free layercapping layer structure includes a multilayer ferromagnetic free layer and a Hf capping layer on the free layer. The end and closure have channels molded into them radiating from a port and opening toward packing material such as silica beads or porous polymeric plugs. The second surface topographical analysis is compared with the first to evaluate the surgical laser.