https://www.zhongheindustry.com/products/en-13889-shackle.html EN 13889 Shackle BS EN 13889 specifies the design, materials, testing, and marking requirements for shackles used in lifting applications. It requires that the shackles be manufactured from high-quality materials and meet certain strength and durability criteria. The standard also specifies testing procedures to ensure that the shackles can withstand the loads and forces they are designed to carry.