Crosby® Screw Pin Sling Saver Shackle | S-281 - 4.5 TonCrosby S 281 4. 5 Ton Web Sling Shackles Built for Better Sling Support and Load Control The Crosby S 281 4. 5 Ton Web Sling Shackle offers enhanced sling compatibility and lifting performance. Its squared bow increases the bearing surface area, allowing for better load distribution across synthetic slings. This improved contact zone prevents bunching, maximizes lifting efficiency by at least 15%, and helps maintain 100% of the slings rated Working