Description 3/4″ 4.75 Ton Forged High Carbon Heat Treated Anchor Shackle with Forged Alloy Screw Pin, Design Factor 6 to 1, All 100% crack detection during manufacturing, All cycle fatigue rated to 1.5 times Work Load Limit. Type 4A, Grade A, Class 2. Screw Pin Type Anchor Shackles Meet the Performance of Federal Specification RR-C-271D.