A blow bar for inserting in a holder of a rotor of an impact crusher defines a longitudinal axis in a z-direction, a vertical axis in a y-direction, and a transverse axis in a x-direction. The blow bar includes two rectangular heads respectively arranged at upper and lower ends of the blow bar and defining there between a middle region, in which the longitudinal axis centrally determines a position of a y-z plane. Each head has side surfaces extending parallel to the y-z plane and parallel at a first spacing to define a thickness between the side surfaces. The two heads are situated offset to the y-z plane in opposite direction by a second spacing in the transverse direction, thereby forming support shoulders in a transition to the middle region. The middle region has a thickness which is not less than the first spacing of the side surfaces.