Harken 150 mm Black Magic, AirBlock Single swivel Cat. No. HAR 3021 Weight 5 lbs
3021 150 mm Block
150 mm AirBlocks®
feature Torlon® rollers in a self-contained center
cage. Rollers stay parallel for low-friction efficiency. UV-resistant,
carbon-black Delrin® balls carry sideloads.
Used on offshore boats, these blocks offer a no “climb-out” deep groove
sheave with radiused edges to protect line. Sculpted aluminum
sideplates and thin-profile sheaves make these blocks very lightweight.
No stainless-to-aluminum contact prevents corrosion.