Series 40 Ball Bearing Block - Triple - Swivel HeadFeatures:Low friction Acetal or Torlon; bearing systemLightweightCheek cut-outs for easy bearing maintenanceFeatures a swivel shackle head for full 360° rotationSheaves running on Acetal or Torlon; ball bearings provide high performance & low friction. The 2-stage ball bearing system provides consistent performance over the full load range.Applications:MainsheetHalyardVangSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)Materials:Acetal ball bearingsUV stabilised Acetal sheaveGrade 316 stainless steel load strap and head fittingImpact and UV resistant, fiber reinforced Nylon cheeks