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Harken 57mm Black Magic Air Low-Load Double Block

$860.95 incl GST


Harken 57mm Black Magic Air Low-Load Double Block are a top favourite of Big Boat performance racers and cruisers. These lightweight, free-running, powerful performers are used for sail controls that see lots of action: mainsheet, runner, halyard, and spinnaker systems. A centre cage keeps Torlon® roller bearings separated and parallel to reduce friction. Shackle blocks lock in two directions or swivel to keep line from twisting.

Low-load blocks have red isolators. They use Torlon® rollers and 316 stainless steel shackles. Standard blocks have 17-4 PH stainless head posts.

Torlon is a registered trademark of Solvay Advanced Polymers L.L.C.


SkuNameSheave Ø mm (in)Length mm (in)Weight g (oz)Maximum line Ø mm (in)Maximum working load kg (lb)Breaking load kg (lb)Shackle pin Ø mm (in)
322857 mm Black Magic Air Aluminium Low-Load Double Block — Swivel57 (2 1/4)132 (5 3/16)342 (12.05)12 (7/16)1250 (2755)2500 (5510)8 (5/16)

Additional information

Weight .6 kg