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 45mm x 13mm (1 3 /4 x 1/2") Fiddle 30/58mm x 13mm (1 3 /16 x 2 1/4" x 1/2") Max rope diameter 10mm ( 3 /8") SWL 400Kg (881 lbs) Break load 800Kg (1763 lbs)