Methods and devices are provided for using a bone anchor driver for driving inner and outer set closure mechanisms or set screws into a bone anchor assembly. In one embodiment, a bone anchor driver is provided that includes an outer shaft configured to engage an outer set screw coupled to a bone anchor assembly, an inner shaft disposed within the outer shaft and configured to engage an inner set screw coupled to the bone anchor assembly, and a torque limiting mechanism configured to automatically switch between a first position in which it is disengaged from the inner shaft and is engaged with the outer shaft, and a second position in which it is disengaged from the outer shaft and is engaged with the inner shaft.