Schaefer Single Stainless Steel Block - 51mm Sheave

The Schaefer Single Stainless Steel Block with 51mm Sheave is a compact marine rigging component engineered for controlled load transfer on sailboats, fishing vessels, and rescue applications. Built by Schaefer Marine—a trusted name in precision deck hardware—this single block combines stainless steel cheeks with a Delrin sheave to deliver smooth operation and reliable holding power in salt-air environments where corrosion resistance is critical.

The 51mm (2-inch) sheave diameter accommodates rope up to 7/16 inch, while the 1,750-pound safe working load (SWL) makes this block suitable for mid-range mainsheet, jib, or halyardrigging on boats between 25 and 40 feet. The compact footprint—4 13/32 inches long by 2 1/8 inches wide—fits tight cockpit spaces without sacrificing structural integrity. The Delrin sheave material reduces friction and noise compared to bronze alternatives, extending bearing life and minimizing maintenance cycles on extended cruises or commercial operations.

Weekend sailors, offshore cruisers, and commercial fishing operations rely on single blocks like this for control-line systems where load angles remain below 120 degrees. The stainless steel construction withstands constant UV and saltwater exposure without pitting or discoloration, eliminating the need for protective coatings. At just 7.1 ounces, this block minimizes weight aloft—a critical factor for performance sailors managing trim and stability. Whether you're replacing worn hardware on a classic sailing vessel or building out a new rigging system, this Schaefer block delivers the corrosion resistance and durability expected from a manufacturer with decades of marine engineering expertise.