Harken Black Magic Blocks

The entire line of Black Magic® AirBlocks® has been redesigned with a sleek new look. Their unique, performance-packed engineering remains exactly the same.

These strong, lightweight blocks feature  free-rolling, high-load Torlon® roller bearings for a high strength-to-weight ratio. Use them for sail controls that see lots of action: mainsheet, runner, halyard, and spinnaker systems.

AirBlocks® are easy to clean and service. They have few parts and no loose balls or rollers to misplace. Unlike blocks that are riveted, fasteners allow quick disassembly with a single hex wrench.

Low Friction Caged Bearings
The center cage keeps Torlon® roller bearings separated and parallel to reduce friction. Dirt and salt falls between rollers. Captive Delrin® balls carry sideloads.

Strong Lightweight Sideplates and Sheaves
6061-T6 aluminum sideplates are CNC-sculpted to remove excess weight. Thin-profile, deep-groove aluminum sheaves have radiused edges to protect high-tech line.

Long-Lasting Protective Finish
Sheaves and sideplates are deep-saturation Hard Lube-anodized for strength and durability. UV-stabilized and PTFE-impregnated for maximum protection and a smooth, slippery surface.