Size 3 Single Plain Bearing Block with SwivelBarton plain bearing blocks have a precision molded acetal sheave running on a large diameter brass bearing, ensuring free running under the highest of loads.Features:Fully swiveling head with removable shackleFor use on dinghies, day boats, and light cruising yachtsSpecifications & Dimensions:Length: (mm) 100 / (inch) 3-15/16"Weight (grams): 73 g.Single (mm) 45 x 13 / (inch) 1-3/4" x 1/2"Max Rope Diameter: (mm) 10 / (inch) 3/8"SWL: (kg) 400 / (lbs.) 881Break Load: (kg) 800 / (lbs.) 1763Note: break loads where break and safe working loads are stated, it is assumed that all sheaves are evenly loaded as in a purchase tackle