This great little piece of hardware will give you indication of status via 4 extremely bright LED's, so bright they might even burn a hole in your retinas!
Easily configured to use with APM 2.5 or 2.6
There are four 3W led White/Red/Green/Bule on the board,
Thanks to Nico Darrow and his post,install video here
Dimension: 57 x 20 x 8mm
Input: 5~30V input.