For seeing into cavities / spaces that are inaccessible e.g. inside walls, floors and ceilings, chimneys etc. Has it's own LED illumination with different brightness settings, and can take pics and video.
Try this YouTube review / demo:
https://www.youtube.com/watch?v=LTIlHIq9s5A
Dual lens - Focal lengths:
Main lens 30mm to 80mm.
Side lens 20mm to 50mm.
Camera diameter 8mm.
Length of flex 5 meters.
The Edinburgh Tool Library
http://edinburghtoollibrary.org.uk
http://edinburghtoollibrary.org.uk