The re-useable Swivel-Grip™ is used to install power cable and has a built-in swivel. The Swivel-Grip™ is constructed out of stainless steel with a radial bearing for bending load and a thrust bearing for tensile load. Grip is obtained by cutting away the cable jacket, feeding the core through the Cone nut and driving the tapered insert into the cable core. The higher the load, the further the insert is drawn into the tapered bore and the firmer the grip becomes. Note that this product is not designed to run around bullwheels.
Swivel-Grip Kits are also available. Read about them here.