There are tools every wrench needs โ€” say, wrenches, for example โ€” and then there are tools that only the geekiest of garage dwellers would even consider welcoming into their toolboxes. What's the nerdiest car gadget imaginable?

How valuable is knowing the precise thickness of a car's paint? I'd say pretty valuable if you're about to bid on a high-end classic, whose owner insists is the "ultimate survivor." Maybe you just want to see how many coats of PPG have been slathered onto that beater in its troubled lifetime โ€” just because. Then you, my friend, need a paint thickness tester. Although thickness testers come in both mechanical (which, thanks to its pen-like size, would look great in a pocket protector) and electronic flavors, we prefer the electronic version for sheer nerditude and the potential of hours of fun for serious collectors and straight-up nerds alike.

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