Jon, the L-Nav is generally two boxes. The 80 mm control with LCD display (audio is in this part), and an either 57 or 80 mm traditional variometer needle display. You can certainly use just the 80 mm control and display box, as the audio is built in to this. It becomes a bit more useful if you also have room for the traditional variometer needle display.

Are you just wanting a stand alone audio variometer? Just sounds, no needle display or anything similar? That is what you asked about but it seems to me all offers have been for more than this.

Steve Leonard