Kestrel Meters come with a couple of different backlight options:

Aviation Green Electroluminescent Backlight

NV - Visible Red Electroluminescent Backlight

All offer automatic or manual activation. The Red display is only available on 4000 and 4500 models and is designated as NV.

My iphone photo really does not give it justice, this is more green in person, much like the color you would see of an "electroluminescent" back lit watch. It defiantly gives off    some light. This is the NV.. My iphone photo really does not give it justice, this is more red in person, very easy to read, but gives off just enough back light to read the display, almost no light leakage.
Why I'd want Green: Cheaper, brighter, gives off a little    light, trouble reading small LCD displays Why I'd want Red: Harder to spot by others, does not diminish night vision, military or night ops usage