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Ronstan Series 55 Ball Bearing Orbit Block

  • Type: Fiddle Block with Becket, Cam Cleat, & Swivel Head
  • Safe Working Load: 1100 lb.
  • Maximum Line Size: 3/8"
  • Item #: 
    Model #: 


    Shipping Weight: 
    0.55 Lbs.
    List Price: 
    Status:  null In Stock

    Quantity : 


    Ronstan Ball Bearing Orbit Blocks™ boast the highest strength-to-weight ratio available. This is achieved through all-composite reinforced polymer materials and a Dyneema® rope link head. Their precision design allows the optimum number of ball bearings in loaded areas and eliminates them in inactive areas. Ineffective mass is reduced even further through fiber-reinforced composites in the block head, cleat arms and beckets.


    • Ultra Lightweight
    • Low friction 2-stage Orbital ball bearing system
    • Highest working load in its class
    • Low profile and compact
    • High performance cleating


    • Mainsheet systems on dinghies, sportsboats and small keelboats to 9m (30ft)
    • Spinnaker sheets on dinghies, sportsboats and small keel boats to 9m (30ft)
    • Halyard, Vang and Backstay application on boats to 8m (26ft)
    • Control line applications on larger yachts


    • Sheave: 2-5/32" + 1-3/8"
    • Max. Line Size: 3/8"
    • Max. Working Load: 1100 lbs.
    • Breaking Load: 2200 lbs.
    • Weight: 8.4 oz.

    Materials :

    • Ball bearings - High compression strength carbon black Acetal
    • Stage 2 bearing - Carbon fiber reinforced, PTFE impregnated Nylon
    • Frame/Cheeks - Toughened, glass fiber reinforced Nylon
    • Rope Link: UV stabilized, multi-strand SK75 Dyneema®

    Note: Fiddle sheave has a high load full contact bearing (ie. not ball bearing). Main sheave has two-stage, ball bearing.


    Ronstan Boom Vang Kit
    Item #: 602530
  • Purchase: 4: 1, Max. Working Load: 400 kg (882 lbs)
  • Boat Size: Up to 30 Feet
  • Snap Shackle Attachment, Includes 30 feet of 5/16" Line
  •  Include
    Model #:
    Spinlock XAS Single Powerclutch
    Item #: 614517
  • Line Size: 4 mm to 8 mm (5/32" to 5/16")
  • Working Load Limit: 400 kg (880 lbs)
  • Reliable All-Around Performance for Low-Load Smaller Diameter Lines
  •  Include
    Model #:

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