57 mm Black Magic®
Used on offshore boats, these strong, lightweight blocks feature Torlon® roller bearings for strength and reduced wear. Rollers are housed in a center cage and stay parallel for low-friction efficiency. Sculpted hardcoat-anodized aluminum sideplates protect sideload ball bearings. Dissimilar metals are isolated to minimize corrosion.
Torlon® is a registered trademark of Solvay Advanced Polymers.