Portable chain vises set up on a level, flat, solid floor wherever they're needed for pipe threading, cutting, and welding. Their base provides a stable footing to resist tipping. They tighten their chain around pipe to lock it down and prevent rolling or shifting. The chain holds irregularly-shaped materials that might be unstable in a yoke vise or V-head stand. A pipe rest at the back of the vise supports pipe along its length. Additional support may be required for long pipes.