These patented devices revolutionized pulley use when they were introduced in 2005. The Omni-Block combines a pulley with a swivel and offers tremendous advantages. It can replace a conventional pulley, carabiner & swivel and is lighter, less expensive and saves valuable vertical space. It also allows installing/removing the rope while the pulley is still anchored.While the standard version serves the needs of most users, the Omni is also available with some specialized options.