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When a sharp deflection in otherwise planar anisotropic laminated material of constant orientation occurs, it is called a kink-band. Kink-bands are also produced by flexural slip like chevron folds. The axial plane of a kink-band is the plane that bisects the angle between deflected and un-deflected portions of the layers and is usually called a kink plane. Kink-bands normally occur on a small scale such as the scale of a hand specimen or on microscopic scale or even on the electron microscopic scale or on the scale of an atomic lattice of a mineral  When these structures are developed on large scale outcrops or on the mappable scale, they are called monoclines. Two kink-bands in opposite directions may join to form what are known as conjugate kink-bands, or if developed on larger scales, conjugate or box folds. The axial planes of conjugate kink bands occur in pairs and are either inclined towards each other (antiforms) or away from each other (synforms) and the obtuse angle between them faces the direction of maximum shortening in rocks or it faces the direction of maximum principal compressive stress s1 . Thus the conjugate kink-bands are important in the sense that they allow the orientations of principal stresses to be determined simply by plotting orientations of axial planes on an equal area net as in case of conjugate shear zones. . Modified after Jiang.