在横截面垂直于纵向方向观察时，所述扁平钢丝圆角矩形，该横截面的短边为2mm或7毫米或更小，横截面的长边等于或小于8mm超级56毫米，对于短边 长边的比为4个超级8或更小，不小于1900兆帕的抗张强度，扭转值不小于12倍。

This flat steel wire is rounded rectangle when viewed in cross section perpendicular to the longitudinal direction, the short side of the cross section is at 2mm or more than 7mm, the long sides of the cross section is not more than 8mm super 56 mm, for the short side the ratio of the long side is at 4 super 8 or less, a tensile strength of not less than 1900 MPa, twisting value is not less than 12 times.