Fiberscopes (fiber optic borescopes) are useful inspection devices in the automotive field. Auto technicians and automotive warranty inspectors are discovering new uses for fiber optic borescopes everyday. Engine combustion chambers are accessed through the spark plug holes to check for damage to valves and pistons without the removal of the heads. Some of the less obvious uses for automotive applications are:
We have noticed an increase in sales to other fields besides automotive. HVAC technicians use fiberoptic borescopes to inspect for mold in ducts and on evaporator coils. Law enforcement uses them to check for contraband and controlled substances under rear seats, consoles and trim panels. Plumbers use fiber optic bore scopes to pinpoint the source of leaks and identify the cause of blocked drains. Electricians use fiberoptic borescopes to see snaked wires through walls, some even attach a hook to retrieve the wire once it is spotted. Exterminators and home inspectors use fiber optic borescopes for termite inspections. Exterminators also use this tool for follow up after an application to verify its effectiveness. Welders use borescopes to check inside vessels or tanks to look for "burn through". Carpenters use them to check walls for plumbing or electrical before using fasteners.
The best borescopes can be found here