The level of the lifting chain is mainly the surface of the surface, the higher the level, the higher the gravity and pulling force. The common levels in China are level 80, 70, and level 43. If it is exported, it is divided into US standards and moral standards. The chain is divided into many specifications, and the uses are also very different. For example, the 6mm, 8mm, and 10mm specifications of level 80 are often used as the main accessories for ring chain gourds. This specification of 13mm has also been well used in the scratch machine industry. Or the chain is used as the main component when making a ring chain crane, and different specifications are selected according to the requirements of the load.