Compact furling line guide system; Reduces line friction during furling; Sheave model WL/2 for line entry and exit stanchions with unique tracker-ball angle adjuster for perfect sheave alignment; Complete with fastenings - easy to fit; Replacement sheave for WL/2 available; Line Diameter: Up to 12mm (1/2"); SWL at Max Line Diameter: 300kg (660lbs); Fasteners: Integral, to fit stanchions 25mm (1") diameter; Weight: 70g (2.5oz)