Shackle / Seal is a lifting tool made of mild steel, carbon steel, alloy steel and Stainless steel 304 & 316. This Shackle / Seal function is to connect or link the sling to the lifting object. Shackles / Seals are usually used to lift goods, baskets, beams, machines, and other heavy lifting objects so that they must use slings and shackles as lifting aids.