The rope is generally divided into round ropes (such as hollow ropes, elastic ropes, core ropes, etc., the characteristics of the tower doors are round, double-layered), flat belts (such as curved belts, flat belts, three-color flat belts, Color flat belts, etc., which are characterized by solid flat belts, all of which are single-layered), and mother-child belts (the mother-of-pearl belt is a ribbon with a round side and a rounded bone called a mother-of-pearl belt)