Barton plain bearing blocks have a precision moulded acetal sheave running on a large diameter brass bearing, ensuring free running under the highest of loads. Single 54mm x 17mm (2 1 / 8 x 5 / 8 ") Fiddle 38/64mm x 17mm (1 1 / 2 x 2 1 / 4 " x 5 / 8 ") Max rope diameter 12mm ( 7 / 16 ") SWL 750Kg (1650 lbs) Break load 1500Kg (3300 lbs)