Patent ID: 8116038

Claim:
A disk drive comprising: a disk drive base; a spindle rotably coupled to the disk drive base, and a disk attached to the spindle; and a head stack assembly (HSA) including first and second actuator arms; a first head gimbal assembly attached to the first actuator arm, the first head gimbal assembly including a read head; a dummy mass attached to the second actuator arm, the dummy mass including a mounting plate portion defining a mounting plate width, the mounting plate portion including first and second projections; a neck portion defining a neck width and a neck length, a root portion of the neck portion disposed between the first and second projections and defining first and second alcoves between the root portion and the first and second projections, respectively; a distal mass portion defining a distal mass width and a distal mass length; wherein the neck width is less than the mounting plate width and the neck width is less than the distal mass width.