Harken 57mm Aluminum Low Load Black Magic Block w/Swivel

The 57mm Aluminum Low Load Black Magic Block with Swivel is engineered for superior performance in marine sailing applications. Perfect for both racers and cruisers, this block offers lightweight durability and exceptional functionality for various sail control systems.

Key Features

• Durable aluminum construction ensures long-lasting performance in harsh marine environments.
• Swivel capability prevents line twisting, enhancing ease of use and efficiency.
• Center cage design separates Torlon® roller bearings, minimizing friction and ensuring smooth operation.
• Dual-direction shackle blocks provide secure locking, enhancing safety during critical maneuvers.
• Red isolators included for low-load applications, offering additional protection and functionality.

Specifications

Feature	Specification
Sheave Diameter	57mm / 2-1/4in
Length	119mm / 4-11/16in
Weight	154g / 5.44oz
Shackle Pin Diameter	6mm / 1/4in
Maximum Line Diameter	12mm / 7/16in
Maximum Working Load	7/16kg / 1655lbs
Breaking Load	1500kg / 3300lb

Benefits

• Enhances the performance of sail control systems, ensuring reliable operation under demanding conditions.
• Lightweight design reduces overall rigging weight, contributing to improved boat speed and handling.
• Rust-resistant 316 stainless steel shackles provide durability and longevity, even in saltwater environments.
• Torlon® rollers guarantee reduced friction, allowing for smoother line movement and easier sail adjustments.

Ideal Applications

• Mainsheet systems
• Runner lines
• Halyard controls
• Spinnaker setups
• Other high-action sail control systems

Quality Assurance

Black Magic Air blocks are trusted by top-tier marine enthusiasts and professional sailors alike. Each block is crafted with precision, utilizing Torlon® rollers and high-grade 316 stainless steel components to ensure maximum performance and resistance to the corrosive marine environment. The center cage design further enhances the block's efficiency by maintaining optimal roller alignment and reducing wear.

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

Orders of physical products placed by 3 PM EST M-F typically ships the same day, if all requested items are in stock. Weekend orders will typically ship on Monday.

Shipping takes 2-7 days.

We currently ship to the Contiguous 48 States.

Life of Sailing merch is custom made for the customer after an order is placed. Total turnaround is typically 7-14 days from order to doorstep.