Designated the shape of the shackle: IVA (Anchor Shackle), IV B D or (Chain Shackles. This two shackle types are used for lifting and are covered by Fed Spec RR-271F. The Pin diameter is larger than the body diameter
Bow Shackles: Have larger shackle body per given size and are often good for use on Bridles, usually available in Stainless Steel , are hard to find in Carbon Steel and we could not locate a heavy duty variety. The pin diameter is the same as the body diameter.
There many more shackle types, but these are the most commonly to be used in anchoring systems.
Designates the type of pin and pin to shackle body latching
Grade A ,Regular Carbon Steel All reputable shackles should have: Size, Working Load Limit shown as permanent marking on body and pin
Grade B Heavy Duty Alloy Steel Bodies and pins forged from alloy steel, heat treated and tempered to give greater strength and abrasion resistance Size, Working Load Limit and traceability codes shown as permanent marking on body and pin