The invention includes sliders provided with indented surfaces, reducing the roll center for head gimbal assemblies below the effective thickness of the slider. Head gimbal assemblies built with these sliders may reduce off-track displacements induced by disk vibration. The load beam gimbal may contact the indented surface, creating a slider roll center less than the slider thickness. Alternatively, the sliders may include a slider contact cover interfacing to the load beam forming the gimbal. The slider contact covers may couple with the slider through an indented surface located closer than the slider thickness. These may have a negative slider roll center. The invention includes actuator arms, actuator assemblies, and hard disk drives including these head gimbal assemblies. The invention includes making the invention's sliders, head gimbal assemblies, actuator arms, actuator assemblies, and hard disk drives. The invention includes the products of these processes.