The Small Boat Classic Block Range from Harken is Ideal for Small Sailboats up to 25 Feet. Strong, dependable, and exceptionally free running, these blocks are the foundation of the Harken line, with a vast library of hardware choices available to complement your boat’s style. Classic blocks come in multiple sizes, dozens of configurations and are ideal for almost every trimming task. Ball bearings, sheave, and sideplates are UV-stabilized with carbon-black for maximum protection. Stainless steel straps reinforce blocks and resist corrosion. Available in 29 mm, 38 mm, and 57 mm sizes in a variety of configurations.