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April 03, 2025 5 min read

HARKEN 29MM BLOCKs at sailing chandlery

Harken 29mm blocks are the most popular and most used blocks in the Harken block range. The 29mm blocks can be found fitted to new boats or, if you are upgrading an older boat. They are lightweight, strong, reliable and affordable.

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HARKEN 29MM BLOCK range

Harken 29mm Carbo Air Block with Swivel - 340

Low-friction Harken 29mm Carbo AirBlocks® from Harken are lightweight, strong, reliable and affordable.


The 29mm block is the most popular Harken product Sailing Chandlery sell and is perfect for halyards and control systems.


Specification

  • Sheave Ø - 29mm
  • Length - 66mm
  • Weight - 26g
  • Shackle Pin - 4mm
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg

Harken 29mm Carbo Block with Swivel and Becket - 341

This low friction 29mm Harken carbo block with becket is compact, lightweight, strong and reliable. 


It is ideal for sailboards, smaller dinghies, and lightly loaded control lines on boats of all sizes.


This version of the Harken 29mm block has a swivel head and becket on the bottom.


Specifications

  • Sheave Ø - 29mm
  • Length - 78mm
  • Weight - 28g
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg

Harken 29mm Double Block - Swivel - 342

The popular Harken 29mm block with two blocks and a swivel feature at the top.


Ideal for purchase systems which need to be flexible.


Specifications

  • Sheave Ø (mm) - 29mm
  • Length (mm) - 73mm
  • Weight (g) - 51g
  • Shackle pin Ø (mm) - 5mm
  • Maximum line Ø (mm) - 8mm
  • Maximum working load (kg) - 299kg
  • Breaking load (kg) - 737kg

Harken 29mm Double Block - Swivel with Becket - 343

The popular Harken 29mm block with two blocks a swivel feature and becket.


Ideal for purchase systems which need to be flexible.

Specifications

  • Sheave Ø (mm) - 29mm
  • Length (mm) - 85mm
  • Weight (g) - 54g
  • Shackle pin Ø (mm) - 5mm
  • Maximum line Ø (mm) - 8mm
  • Maximum working load (kg) - 299kg
  • Breaking load (kg) - 737kg

Harken 29mm Triple Carbo Block With Becket and Cam Cleat - 347

This Harken triple 29mm carbo block set comes complete with a becket and cam cleat. Popular for use in kicker systems on dinghies.


Specifications

  • Sheave Ø - 29mm
  • Length - 29mm
  • Weight - 133g
  • Maximum line Ø - 6mm
  • Maximum working load - 408 kg
  • Breaking Load - 816kg
  • Shackle pin Ø - 5mm

Harken 29mm Carbo Air Block - 348

Low-friction Harken 29mm Carbo AirBlocks® from Harken are lightweight, strong, reliable and affordable.


The 29mm block is the most popular Harken product Sailing Chandlery sell and is perfect for halyards and control systems.


Specification

  • Sheave Ø - 29mm
  • Length - 49mm
  • Weight - 23g
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg

Harken 29mm Stand Up Carbo Air Block - 349

Harken low friction 29mm Carbo AirBlock which is lightweight, strong, reliable and affordable.


This Harken block comes with a spring and bracket to hold the block in an upright position.


Specification

  • Sheave Ø - 29mm
  • Length - 56mm
  • Weight - 31g
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg


Eye Strap Specifications

  • A (mm) - 43mm
  • B (mm) - 12mm
  • C (mm) - 32mm
  • D (mm) - 11mm
  • E (mm) - 10mm
  • F (mm) - 11mm
  • Weight (g) - 4.5g
  • Fasteners (mm) - 5mm
  • Breaking load (kg) - 726kg

HARKEN SINGLE 29MM CHEEK BLOCK 350

29mm Harken Cheek Blocks are low friction Carbo Air blocks which mount to the deck of your boat. They are lightweight, strong and reliable.


Specifications

  • Sheave Ø - 29 mm
  • Length - 53 mm
  • Weight - 17 grams
  • Maximum line Ø - 8 mm
  • Maximum working load - 150 kg
  • Breaking load - 454 kg

Harken 29mm 90 Degree Block - 352

A low friction 29mm carbo air blocks that is lightweight, strong and reliable. 


This small and compact block has a very high working loads for safe and easy trimming on your sailing dinghy.


The metal head on this block can move up to a 90 degree angle to allow the block to move freely from different sheeting angles.


Specifications

  • Sheave Ø - 29mm
  • Length - 52mm
  • Weight - 26g
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg

29mm Harken Double Traveler Block - 353

Low friction Harken 29mm Carbo AirBlocks® are lightweight, strong, reliable and affordable. 


These small, compact blocks have very high working loads for safe, easy trimming on your boat.


These Harken 29mm blocks are joint together to allow a purchase system running in two different directions or at different angles. Perfect for traveller systems.


Specifications

  • Sheave Ø - 29mm
  • Length - 92mm
  • Weight - 34g
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg

29mm Harken Crew Block - 371

Low friction Harken 29mm Carbo AirBlocks® are lightweight, strong, reliable and affordable. 


These small, compact blocks have very high working loads for safe, easy trimming.


These two blocks are joint with a metal ring to allow for a flexible double purchase system pulling in different directions. 


Rope can also be tied to the ring to keep the blocks in position.


Specifications

  • Sheave Ø - 29mm
  • Length - 124mm
  • Weight - 51g
  • Maximum line Ø - 8mm
  • Maximum working load - 150kg
  • Breaking load - 454kg

Harken 29mm Double Block - 381

This Harken 29mm double block creates low friction and is lightweight, strong and reliable. 


These small, compact blocks have very high working loads for safe, easy trimming.


\Ideal for a mainsheet or jib purchase system.


Specifications

  • Sheave Ø - 29mm
  • Length - 54mm
  • Weight - 34g
  • Maximum line Ø - 8mm
  • Maximum working load - 299kg
  • Breaking load - 737kg

Harken 29mm Pivoting Lead Block with Cam-Matic Cleat - 395

Harken high strength pivoting lead blocks with cam cleats are used for halyard controls on larger keelboats and as “head knockers” on dinghies and beachcats for sheeting directly from the boom.


 They are also seen on catamaran masts for kite hoists and cleating.


Hole spacing and rivet size are the same as Classic models, making upgrades easy. The cam cleat can be reversed for either up or downward cleating.


Please note: This product comes with a lead time expected to be up to 10 working days.


Specifications

  • Sheave Ø - 29mm
  • Length - 100mm
  • Weight - 90.7g
  • Maximum line Ø - 6mm
  • Maximum working load - 91kg
  • Breaking load - 295kg

Footnote - Maximum working loads and breaking loads for blocks based on cam strengths.