Black Magic® Airblocks evolved from custom blocks developed for top-level syndicate racers. Today, these free-rolling blocks have become part of Harken's standard line and used on boats from club racers to elete racing machines.

Sculpted, Hardkote anodized sideplates with Teflon® impregnation. Radiused edges to protect line. No climb-out deep-groove sheaves. Center-caged captive Torlon® rollers reduce friction–no roller-to-roller contact. Carbon-black Delrin® balls in captive race. Dissimilar metals isolated–no corrosion. Three-way head system