51mm Thru-Deck High-Strength Block
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HARKEN51mm Thru-Deck High-Strength Block


In stock online.
Model # 359752 | Mfg # 310UPC # 97653010319
51mm Thru-Deck High-Strength Block




51mm Thru-Deck High-Strength Block

Name Value
Ball Bearings Delrin
Becket No Becket
Diameter 3/16 Inch or 5 mm
Direction Any
Integral Cleat No Integral Cleat
Mount Type Mechanical Fasteners
Ratchet Non Ratcheting
Safe Working Load 2000 Pounds
Sheave Diameter 50 mm
Type Single Thru-Deck
Weight 5.75 Ounces

Product Overview

Harken 51mm Thru-Deck High-Strength Block allows lines through the deck and bulkhead.

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
  • Use for control lines
  • Sheave Diameter: 2" (51 mm) 
  • Max. Wire Diameter: 3/16" (5 mm)  
  • Max. Working Load (MWL): 2000 lb. (907 kg)  
  • Breaking Load: 4000 lb. (1814 kg)   
  • Weight: 5.75 oz. (163 g) 


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