Sale 57mm Black Magic® Block, Double
Mouse Over to Zoom
Click to Enlarge

HARKEN57mm Black Magic® Block, Double


20% Off - Ends 03/29/20

Regular $325.99

In stock online.
Model # 14136030 | Mfg # 3228UPC # 97653264682
57mm Black Magic® Block, Double




57mm Black Magic® Block, Double

Name Value
Becket No Becket
Diameter 7/16 Inch or 11 mm
Direction Any
Integral Cleat No Integral Cleat
Length 5 3/16 Inches
Mount Type Swivel Shackle
Ratchet Non Ratcheting
Safe Working Load 2755 Pounds
Sheave Diameter 57 mm
Type Double
Weight 10.1 Ounces

Product Overview

Harken 57mm Black Magic® Double Block allows a 2:1 or 3:1 purchasing system.

The entire line of Black Magic® AirBlocks® offer a sleek and polished look. Their unique performance engineering remains the staple of the Black Magic line of blocks. These strong, lightweight blocks feature free-rolling, high-load Torlon® roller bearings for a high strength-to-weight ratio. Used for dynamic high load sail controls including mainsheets, runners, halyards and spinnaker systems.

Air blocks are easy to clean and service. They have few parts and no loose balls or rollers to misplace. Unlike blocks that are riveted, fasteners allow quick disassembly with a single hex wrench.

Key Features

  • Lightweight blocks with high-load Torlon® roller bearings for a high strength-to-weight ratio
  • Ideal for sail controls including mainsheet, runner, halyard, and spinnaker systems
  • Center cage keeps Torlon® roller bearings separated and parallel to reduce friction
  • Sheaves have radiused edges to protect today’s high-tech line
  • Stainless steel swivel shackle
  • Low-load blocks have red isolators
  • Sheave Diameter: 2 1/4" (57 mm)
  • Max. Line Diameter: 7/16" (12 mm)
  • Max. Working Load (MWL): 2755 lb. (1250 kg) 
  • Breaking Load: 5510 lb. (2500 kg)  
  • Weight: 12.05 oz. (342 g)
  • Length: 5 3/16" (132 mm)


The West Advisor articles have answered boaters' questions and provided solutions to boating problems for more than 20 years. West Marine has compiled one of the Web's most comprehensive collections of technical boating information articles.

Related West Advisor Articles


Product Q & A