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 35mm x 12mm (1 3 /8 x 7/16") Fiddle 30/45mm x 12mm (1 3 /16 x 1 3/4" x 7/16") Max rope diameter 8mm ( 5 /16") SWL 370Kg (815 lbs) Break load 740Kg (1630 lbs)