Barton Marine 35mm Diameter Plain Bearing Sheaves. Used throughout the complete Barton block range. Molded from UV-resistant acetal resin the Barton sheave is made to survive the harsh marine environment. The unique super-low friction ball race system runs on a large diameter center boss which ensures an extremely low friction performance. Package Contents: Barton Marine 35mm Diameter Plain Bearing Sheave Barton Marine 64804: 35mm Diameter Plain Bearing Sheaves