These aren't the height of technology. Basically a mirror on a ball joint at the end of a telescopic pole. But I've used one to good effect. It lets you look into places you can't easily stick your head. Mine has a built in LED illuminator. I wonder how I ever did without one.

Wuudi 5PCS Inspection Mirror Set, Magnetic Pick-Up Tool Kit with Telescoping Handle 360 360 Rotatable Including 8 lb/ 1.5 lb Pick-Up Rod, Flashlight and...
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