The patented extruded hole design, in conjunction with the groove profile of the sheave, provides a more powerful grip than conventional designs - up to 20:1 holding power. Unrivalled low weight is achieved by the use of a Torlon^® ratchet pawl, high grade machined alloy sheave and black Acetal hubs and bearings. On-Off switching knob is fitted to both sides of the swivel blocks (one can be removed if desired). Ratchet blocks can be disassembled for sheave replacement with RF62000.Maintains alignment with a variable line entry-angle. The line passes through the centre of the pivot support, remaining as close to the deck as possible. The patented extruded hole design, in conjunction with the groove profile of the sheave, provides a