Product Description

57 mm Black Magic® AirBlocks® are used on offshore boats where weight and performance are critical. They feature free-rolling, large-diameter aluminum sheaves with Torlon® roller bearings housed in a unique center cage. UV-resistant, carbon-black Delrin® balls carry sideloads. Corrosion is minimized by isolating dissimilar metals.

Blocks are Hardkote-anodized and have 17-4 PH stainless headposts and shackles. Easily disassembled. Use it for sheets, halyards, running backstays and control lines.

Part Number: 3227
**Replaces 1965

Imperial Metric
Sheave dia. - 57 mm
Length 4 1/2" 114 mm
Weight w/shackle 7.04 oz 200 gr
Shackle pin dia. 1/4" 6 mm
Max Line dia. 7/16" 12 mm
Maximum Working Load 2500 lbs 1134 kg
Breaking Load 5000 lbs 2268 kg
Fastener Circle 1 15/32" 37 mm
Padeye 1/4" 6 mm


A 2 7/32" 57 mm
B 2 3/16" 56 mm
C 1 1/4" 32 mm

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Harken 57mm HL Standup Block
Original Price: $ 315.25
Price: $ 252.20
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