25mm Single High-Strength Block
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HARKEN25mm Single High-Strength Block


In stock online.
Model # 359679 | Mfg # 300UPC # 97653010210
25mm Single High-Strength Block




25mm Single High-Strength Block

Name Value
Ball Bearings Delrin
Becket No Becket
Diameter 3/32 Inch or 2 mm
Direction Any
Integral Cleat No Integral Cleat
Mount Type Side Shackle
Ratchet Non Ratcheting
Safe Working Load 1000 Pounds
Sheave Diameter 25 mm
Type Single
Weight 1 Ounce

Product Overview

Harken 25mm Single High-Strength Block with high-load composite bearings to carry axial loads.

Harken's Lightweight, low-friction blocks with high-load composite bearings carry wire halyards and control line cascades. Side-load balls reduce friction from twists or unfair leads on 304-311. 300-303 has thrust washers. Blocks open to allow passage of swaged wire. Hard Lube-anodized sheave for strength and corrosion resistance. Cheek blocks include fasteners.

Key Features

  • Impregnated Hardkote anodized aluminum bearings
  • Side-load carbon-black Delrin® washers
  • Polished stainless steel strap type fixed shackle
  • Use for wire halyards, vangs, control lines
  • Sheave Diameter: 1" (25 mm) 
  • Max. Line Diameter: 5/32" (4 mm)  
  • Max. Working Load (MWL): 1000 lb. (454 kg)  
  • Breaking Load: 2000 lb. (907 kg)   
  • Weight: 1 oz. (28 g) 


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