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RONSTAN Series 55 Ball-Bearing Orbit Blocks

The ultimate, next-generation, high-performance blocks incorporate unique innovations including radically new bearing systems, super light, all-composite materials, innovative new head fittings and a sleek design for the highest strength to weight ratio available. The precision design provides the optimum number of ball bearings in critically loaded areas, eliminates them in inactive areas and reduces ineffective mass, creating the "2-stage" bearing system for durability and low friction performance. The flexible Dyneema® rope link is a product of the latest trends in grand prix ocean racing and provides a more flexible, lighter weight and lower profile solution than traditional shackles. It can be set at a 0 or 90 degree orientation, provides stress-free articulation without allowing the block to over-rotate, and is locked in place with a security clip that doesn’t require tools to fit. The Dyneema link is also more compatible with carbon, Dyneema and webbing connection points than steel loop tops or shackles.

  • Sheave: Carbon-fiber reinforced, PTFE-impregnated engineered nylon
  • Bearings: High-compression–strength Carbon Black Acetal; Stage 2 Bearing: Glass fiber-reinforced, MoS2-impregnated engineered nylon
  • Sheave Size: 2-5/32" (55mm)
  • Line Diameter: 3/8" (10mm) max.
  • Cheek Material/Finish: Toughened glass fiber-reinforced nylon
  • Shackle/Strap Type: UV-stabilized, multi-strand Dyneema rope link
Customer Reviews
Product Models
Description WM Model # MFG Part # Availability Price Quantity  
Ball-Bearing Orbit Block, Single/Becket/Swivel Head, 1,100lb. SWL, 3.1oz. 11075363 RF55110
In stock online.

Reg. $41.61

Save $4.17

$37.44

Ball-Bearing Orbit Block, Cheek, 1,100lb. SWL, 2.6oz. 8738676 RF55151
In stock online.

Reg. $35.02

Save $3.51

$31.51

Ball-Bearing Orbit Block, Upright Lead, 1,100lb. SWL, 3.2oz. 8738684 RF55171
In stock online.

Reg. $49.05

Save $4.91

$44.14

Ball-Bearing Orbit Block, Double/Becket/Swivel, 550lb. SWL 11075397 RF55210
In stock online.

Reg. $84.96

Save $8.50

$76.46

Ball-Bearing Orbit Block, Double/Becket, 1,765lb. SWL, 4.9oz. 8738643 RF55211
Limited availability.

Orig. $72.99

Now  $49.77

Ball-Bearing Orbit Block, Triple/Becket/Swivel, 1,650lb. SWL 11075405 RF55310
In stock online.

Reg. $110.46

Save $11.05

$99.41

Ball-Bearing Orbit Block, Quad/Becket/Swivel, 1,650lb. SWL 11075413 RF55410
In stock online.

Reg. $169.96

Save $17.00

$152.96

Product Description

The ultimate, next-generation, high-performance blocks incorporate unique innovations including radically new bearing systems, super light, all-composite materials, innovative new head fittings and a sleek design for the highest strength to weight ratio available. The precision design provides the optimum number of ball bearings in critically loaded areas, eliminates them in inactive areas and reduces ineffective mass, creating the "2-stage" bearing system for durability and low friction performance. The flexible Dyneema® rope link is a product of the latest trends in grand prix ocean racing and provides a more flexible, lighter weight and lower profile solution than traditional shackles. It can be set at a 0 or 90 degree orientation, provides stress-free articulation without allowing the block to over-rotate, and is locked in place with a security clip that doesn’t require tools to fit. The Dyneema link is also more compatible with carbon, Dyneema and webbing connection points than steel loop tops or shackles.

  • Sheave: Carbon-fiber reinforced, PTFE-impregnated engineered nylon
  • Bearings: High-compression–strength Carbon Black Acetal; Stage 2 Bearing: Glass fiber-reinforced, MoS2-impregnated engineered nylon
  • Sheave Size: 2-5/32" (55mm)
  • Line Diameter: 3/8" (10mm) max.
  • Cheek Material/Finish: Toughened glass fiber-reinforced nylon
  • Shackle/Strap Type: UV-stabilized, multi-strand Dyneema rope link

Specs

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