Abstract: A gearshift lever (1) for an automatic transmission in a motor vehicle is provided with a knob (4) arranged at the top end of the gearshift lever member. A locking bar (2) is guided axially on the gearshift lever. A manually movable mechanism (5, 7) actuates the locking bar (2) relative to the gearshift lever (1). Two parts of the mechanism (5, 7) have teeth (6, 8) engaging one another. These parts are arranged such that a movement of at least one of the parts (5) toward the locking bar (2) brings about an axial movement of the locking bar (2). At least one of the two toothed segments (6; 8) extends along a curve, and the effective power ratio through a first of two curve radii is greater than the power ratio of the second radius.