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 64mm x 17mm (2 1 /2 x 5/8") Fiddle 44/70mm x 17mm (1 3 /4 x 2 3/4" x 5/8") Max rope diameter 12mm ( 7 /16") SWL 1000Kg (2200 lbs) Break load 2000Kg (4400 lbs)