The steel grade of the anchor chain used for the production of the anchor chain is divided into three grades: M1, M2, and M3 for electric welding, and two grades for cast steel anchor chain, M2 and M3. Add A (such as AM2) before the corresponding code to indicate a gear chain, and B to indicate a stud less chain (with two levels of BM1 and BM2). The higher the steel grade, the greater the tensile strength. AM1 grade anchor chain steel is killed steel, AM2, AM3 grade anchor chain steel is fully killed and fine-grained steel. For the same ship, if steel with high strength is used, the size of the chain link can be appropriately reduced.