A tool that I initially had no idea that I needed when I first started the hobby, but quickly realized I needed one, and with the size parts we normally deal with in RC I knew I needed a precise one. That's where digital comes in.
I have always had a small mechanical set that worked for most things around the house that needed "estimated measurements", but they didn't do the trick for RC.
I picked up a 6 inch, titanium set from Carrera and love them. These do metric, inches, and fractions (not all do) so they have you covered. The 6" set is plenty for what I'll be measuring in my RC workshop.
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