Series 20 Orbit Block
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RONSTANSeries 20 Orbit Block


In stock online.
Model # 10468502 | Mfg # RF25109UPC # 9316800414185
Series 20 Orbit Block


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Series 20 Orbit Block

Name Value
Ball Bearings Stainless Steel
Becket No Becket
Diameter 1/4 Inch or 6 mm
Direction Any
Integral Cleat No Integral Cleat
Mount Type Rope/Webbing
Ratchet Non Ratcheting
Safe Working Load 550 Pounds
Sheave Diameter 3/4 Inches or 19 mm
Type Single

Product Overview

Lightweight and strong block made for rigging systems that use high-tech lines.

Ronstan’s goal for the Orbit block was to produce a block with an excellent strength to weight ratio—and they nailed it. These blocks weigh in at under 9 grams (.3 oz) but can handle 550 lbs safely. Designed exclusively for lashing installation, the Orbit Series 20 eliminates heavy shackle pin posts and unnecessary metals to reduce weight. To maintain the strength Series 20 blocks are known for, the frame and cheeks have been reinforced with glass fiber nylon and are engineered to accept up to 4mm lashing. Efficiency is provided by the proven two-stage bearing system; light to moderate loads are carried by the 316 stainless steel bearings while heavier static loads are shouldered by a slide bearing. Conventional and high-tech lines run smoothly over the UV resistant acetal sheave. Sailors can have their cake and eat it too with lightweight and strong Ronstan Orbit blocks.

Key Features

  • Excellent strength to weight ratio
  • Two-stage bearing system for efficiency for static and dynamic loads
    • 316 stainless steel ball bearings for moderate loads
    • 316 stainless steel slide bearing for higher static loads
  • Designed exclusively for lashing installations (accepts 4mm lashing)
  • UV resistant high-compression acetal sheave
  • Ideal for dinghy control lines

Ronstan Orbit Blocks® Selection Guide

Sheave DiameterLine CompatibilityShackle Pin Diameter (if applicable)
20mm1/4" (6mm)1/8"
30mm5/16" (8mm)5/32"
40mm5/16" (9mm)5/32"
50mm3/8" (10mm)3/16"


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