The N3 Audio is a digital audio altimeter (NOT a visual altimeter), designed to integrate with your mp3 player. You must wear a headset with the N3 Audio as there is no speaker built into the unit.
The features of this unit is similar to the Altimaster N3 except for the alarms. This unit has preset verbal freefall and canopy alarms, freefall and canopy alarm volume is adjustable, it has downloadable wav files and it speaks your current altitude.
N3 Audio is no longer manufactured, but still serviced by Alti-2 subject to availability of parts.