Turnbuckles tighten and secure the cables and provide the necessary tension for a clean look. Use on both ends of the run. For ceiling only. Cables drop 5" from ceiling. Pair. If mounting to metal, order isolating connectors for each pair of turnbuckles (sold separately). INSTALLATION All turnbuckles include mounting hardware for drywall. Special hardware is available for brick, cement, or plaster surfaces (sold separately). For all runs of over twenty feet, turnbuckles should be reinforced with wood blocking behind the wall.