Mine is a "USB Endoscope" model UC100SL. It's got a 36" probe and a 6 foot USB cord. The driver disc is about 3" in diameter and fits a regular laptop computer disc drive.

I'd recommend a digital caliper for quick and dirty measurements of bore size, crankshaft journal diameter, etc. I've got a Starrett brand professional quality digital caliper that cost about $350.00, but they're available for considerably less. Plastigauge is also an option for checking bearing clearance, and all it takes is the width measuring gauge on the envelope the plastic thread comes in to get a pretty accurate idea of oil clearances.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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