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Binks is your stop for all boating and watersport needs
Binks is your stop for all boating and watersport needs

Harken 57mm Double Carbo Block w/Becket (HK2603)

by Harken
Original price $245.86 - Original price $245.86
Original price
$245.86 - $245.86
Current price $245.86
SKU HK2603

Low-friction Carbo Airblocks are lightweight, strong, reliable and affordable. Companion to the popular Harken Black Magic line, these small, compact blocks have very high working loads for safe, easy trimming no matter how hard the wind blows. Sideplates of high strength resin are UV-stabilized to provide excellent protection against long-term exposure to saltwater and sun. Carbo blocks are perfect for the small-diameter lines favored by racers.


  • Blocks are 30% lighter with a 60% higher working load than Classic blocks
  • Open AirBlock design eliminates unnecessary material and weight
  • Ball bearings, sheave, and sideplates are UV stabilized with carbon black for maximum protection
  • Patented switch locks shackle in front or side positions, or lets block swivel to keep line from twisting

The 57mm Carbo has a broad working range. Use for main and jib sheets on centerboard and keelboats like Etchells, Dragons, and J/24s, and mainsheet systems on catamarans.

Use for:

  • Main/jib sheets
  • Mainsheet fine-tune
  • Control lines
  • Vangs
  • Cunninghams
  • Outhauls


  • Sheave: 57mm
  • Length: 142mm
  • Weight with shackle: 187g
  • Shackle pin: 6mm
  • Max line: 10mm
  • Safe working load: 720kg
  • Breaking strength: 1500kg