HARKEN 75mm Aluminum Double Stand-Up Block, HBB254

Black Magic Air blocks are a top favorite 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. Black Magic blocks 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.

Note: Special Order Only

• Shackle blocks lock in two directions or swivel to keep the line from twisting. Set screw allows the shackle to be fixed or to swivel.
• Sideplates are made of aluminum hard cote-anodized for durability and to stay looking as black as their name for years. All the time doing the strength/responsiveness magic we designed into them.
• Easy maintenance, quick disassembly with hex wrench; minimal number of fasteners; no loose balls or rollers.
• Low-friction efficiency for fast trim and release, center cage keeps Torlon® roller bearings separated and parallel to reduce friction. Captive Delrin® ball bearings carry side loads.