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RONSTAN Series 20 Blocks

Two-stage bearing system with stainless-steel ball bearings handles very high safe working loads. Designed for small diameter, high-tech line on high-performance dinghies and control lines on sport and race boats. Each double and triple block offers a formed loop head and extra shackle for mounting versatility.

  • Sheave: Acetal plastic
  • Bearings: Stainless
  • Sheave Size: 3/4" (20mm)
  • Line Diameter: 1/4" max.
  • Cheek Material/Finish: Stainless and textured fiber-reinforced Zytel
  • Shackle/Strap Type: Double/Triple blocks: Two-way 0° and 90° head; single blocks: Loop or swivel shackle
Customer Reviews
Product Models
Description WM Model # MFG Part # Availability Price Quantity  
Series 20 Block, Single Shackle Head, 550lb. SWL, 0.7oz. 1787118 RF20100
In stock online.

$18.79

Series 20 Block, Single with Loop Head, 550lb. SWL, 0.5oz. 1787191 RF20101
In stock online.

$11.29

Series 20 Block, Single with Loop Head/Becket, 550lb. SWL, 0.6oz. 1787209 RF20111
In stock online.

$14.99

Series 20 Block, Single Stand-Up, 550lb. SWL, 0.7oz. 1787217 RF20141
In stock online.

$17.99

Series 20 Block, Cheek, 550lb. SWL, 0.4oz. 1787225 RF20151
In stock online.

$14.49

Series 20 Block, Upright Lead, 550lb. SWL, 0.6oz. 1787233 RF20171
In stock online.

$17.99

Series 20 Block, Pivoting Lead, 550lb. SWL, 1.0oz. 1787381 RF20174
Delivery within 2 - 3 weeks.

$32.99

Series 20 Block, Double with 2-Axis Shackle Head, 770lb. SWL, 1.5oz. 1787241 RF20202
In stock online.

$26.49

Series 20 Block, Double with 2-Axis Shackle Head/Becket, 770lb. SWL, 1.6oz. 1787258 RF20212
In stock online.

$29.79

Series 20 Block, Triple with 2-Axis Shackle Head, 880lb. SWL, 2.2oz. 1787282 RF20302
In stock online.

$37.99

Series 20 Block, Triple with 2-Axis Shackle Head/Becket, 880lb. SWL, 2.3oz. 1787308 RF20312
In stock online.

$39.99

Series 20 Block, Triple with 2-Axis Shackle Head/Becket/Cam, 880lb. SWL, 4.3oz. 1787332 RF20332
In stock online.

$89.99

Series 20 Block, Single Exit with Cover Plate, 550lb. SWL, 0.8oz. 1787365 RF20711
Delivery within 2 - 3 weeks.

$28.99

Product Description

Two-stage bearing system with stainless-steel ball bearings handles very high safe working loads. Designed for small diameter, high-tech line on high-performance dinghies and control lines on sport and race boats. Each double and triple block offers a formed loop head and extra shackle for mounting versatility.

  • Sheave: Acetal plastic
  • Bearings: Stainless
  • Sheave Size: 3/4" (20mm)
  • Line Diameter: 1/4" max.
  • Cheek Material/Finish: Stainless and textured fiber-reinforced Zytel
  • Shackle/Strap Type: Double/Triple blocks: Two-way 0° and 90° head; single blocks: Loop or swivel shackle

Specs

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REVIEW SNAPSHOT®

by PowerReviews
RonstanSeries 20 Blocks
 
5.0

(based on 2 reviews)

Ratings Distribution

  • 5 Stars

     

    (2)

  • 4 Stars

     

    (0)

  • 3 Stars

     

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Reviewed by 2 customers

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(1 of 2 customers found this review helpful)

 
5.0

Great Value!!

By Gary

from Beaufort, SC

About Me Advanced

Verified Buyer

Pros

  • Attractive Design
  • Easy To Install
  • Easy To Use
  • Quality Construction

Cons

    Best Uses

    • Sailing
    • Small Boats

    Comments about Series 20 Blocks:

    Ronstan make excellent products, at excellent prices. They are well made, and always seem to be just the right design for my needs.

    (1 of 1 customers found this review helpful)

     
    5.0

    Excellent Value!

    By Gary

    from Beaufort, SC

    About Me Advanced

    Verified Buyer

    Pros

    • Attractive Design
    • Easy To Install
    • Easy To Use
    • Quality Construction

    Cons

      Best Uses

      • Sailing
      • Small Boats

      Comments about Series 20 Blocks:

      I have found Ronstan products to be excellent value for the money. They are very well made, and seem to have the knack of making just the right part for my needs!

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      Questions about this Product?
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