A turnbuckle is an ingenious mechanical device, which is used to apply tension to a sailboats standing rigging wires, lifelines, and so forth. It is also called bottlescrews. It consists of an elongated metal link, or a tube, with a left hand thread in the other. Thus, when the matching turnbuckle is turned, it will take up slack in an attached wire and maintain tension.

Turning is a process used to produce cylindrical components in a lathe. It can be done manually as well as using a CNC machine. In turning, a cylindrical piece of material is rotated and a cutting tool is traversed along 2 axes of motion to produce precise diameters and depths. Turning can be either on the outside of the cylinder or on the inside to produce tubular components to various geometries.

Turning and Facing Holders is used for holding high speed or carbide square shank tools close to the tool post for more rigidity when turning, facing and threading. It features V-groove holds round shank boring bars and tools as well as square toolbits. Boring bar not included. Precision quick change toolholder will interchange with all leading brands.