Borescope Info ?

Inspection Camera with monitor Video Endoscope Pipe Car Borescope Waterproof | eBay
I have one similar to this one, however mine has more accessories and was a few dollars more...It's at my hangar so I can't tell you the exact brand, but as I said very similar. Mine works great, takes good pictures and easy to use.
Norm

EBay shows some you can plug into your smart phone.