All of Nicro's stainless snap shackles are made of investment cast 15-5 PH stainless steel, which yields a product that has both excellent corrosion resistance AND a high strength-to-weight ratio. The 15-5 PH alloy, which has been well known in the aerospace industry, will provide greater ductility with no sacrifice in tensile strength. C 5/8 E 5/8 L 3 5/8 Deforms at 4990 lb Weight 4.0oz."