From high-quality high-carbon steel rods and pull through Austempering crafted. Prestressing steel wire having a diameter of 2.5 to 5 mm, a tensile strength of 1500 to 1900 MPa, in order to increase the bonding effect and concrete, steel wire, steel wire and strand nicks, steel by roll out regularity dents, Wire is the score. In one of the core wire, 6 wire twisted around its surroundings, that is, 7 shares strand, China is now the most common strand varieties. They belong to the cold working of steel, when used according to the required length can be cut with no apparent yield point, tensile strength of the material can only be based on testing.