Patent ID: 8202255

Claim:
A dose display mechanism for a drug delivery device having a dispensing end, the dose display mechanism comprising: a dose setting dial having a proximal end, a distal end, and an external surface, the distal end being closer to the dispensing end of the drug delivery device than the proximal end, the dose setting dial having an external helical thread and external grooves extending from the proximal end to the distal end, the external surface having indices thereon, the indices being arranged lengthwise along the dose setting dial for visual display of a dose setting of the drug delivery device; and a counter ring having an external surface, the external surface of the counter ring having indices thereon positionable adjacent to the indices on the external surface of the dose setting dial, the indices on the counter ring cooperating with the indices on the dose setting dial to provide a visual display of the dose setting of the drug delivery device wherein the indices on both the counter ring and the dose setting dial are visible, the counter ring being in an interlocking relationship with the external grooves of the dose setting dial such that the counter ring is free to move axially along the external grooves with respect to the dose setting dial while being prevented from rotation with respect to the dose setting dial.