Looking through ads on aso.com, I ran into this picture.
http://www.aso.com/aircraft/77810/panel-1.jpg

What is the instrument in the lower left of the panel underneath the
clock?

It looks a bit like a VSI, but the 0 point is at 12 o'clock instead of
9 o'clock, and it appears to have 3 indicator arms. Also, the scale
isn't symmetric, it runs from -5 to +12.

If it helps - the plane is a Cherokee 180.

Thanks,
Nathan