HARKEN 125mm Aluminium Stand-up Block 16504 Ratchamatic block versions roll freely

Ratchamatic block versions roll freely in both directions under low loads and automatically engage a ratchet mechanism as loads increase

Sheave 38mm

Full 180-degree door opening with solid hinge pin

UV & Weather-Resistant: Featuring colour fastness to light grade 6-7

HARKEN 125mm Aluminium Stand-up Block 16504 Ratchamatic block versions roll freelyBlack Magic Air blocks 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. Sideplates and sheaves Hard Lube anodized for maximum UV protection and a smooth surface. Centre cage keeps Torlon roller bearings separated and parallel to reduce friction. Torlon is a registered trademark of Solvay Advanced Polymers L. L. C.